1. John Ritter -- Perhaps THE saddest of all cases. Ritter, to sitcom viewers, will always be remembered as Jack Tripper on the 1970s sitcom "Three's Company," and as the youngest of 2 sons born to the late cowboy movie actor Tex, but it was while on the set of his comeback vehicle, "8 Simple Rules for Dating My Teenage Daughter," on the afternoon of Thursday, September 11, 2003, that Ritter suddenly fell ill with what he initially thought was food poisoning; instead, at 1 a.m. ET / 10 p.m. PT the next morning, Friday, September 12, 2003, Ritter was dead at age 54. The cause of death -- dissection of the aorta. Ritter's untimely death occurred 5 days before his 55th birthday September 17, 2003; the day after his youngest daughter, Stella, celebrated her 5th birthday; and on the day of his 2nd wife, Amy Yasbeck's, 40th birthday. Besides Amy & Stella, Ritter was survived by 3 grown children (including actor son Jason) from his 1st marriage to Nancy Morgan (which ended in divorce in 1996, in part because of Ritter's relationship with Yasbeck), his mother, Dorothy Fay Southworth (who eventually died the following November 5, 2003 of old age at age 88), and an older brother, Tom, a lawyer who was born disabled by Cerebral Palsy.

2. Nicholas Colasanto -- Although he had a long stage & film career, it was to sitcom viewers that Colasanto will always be remembered as Ernie "Coach" Pantusso on the hit 1980s sitcom "Cheers." On February 8, 1985, after a 2-month absence due to physical illness, Colasanto returned to work on "Cheers," but just 4 days later, on February 12, 1985, Colasanto died of a massive heart attack while watching TV at his California home. The following fall, Coach was written out of the series as also having died, & Woody Harrelson took his place as Woody Boyd, a pen pal of Coach's whom Sam Malone eventually hired to work for him at Cheers.

3. Joseph Kearns -- Although he had a long showbiz career, Joseph Kearns will always be known as Mr. George Wilson on the 1950s sitcom version of "Dennis The Menace." It was on February 17, 1962, hours after the 100th "Dennis" episode was filmed, & ironically 5 days after his 55th birthday on February 12, 1962, that Kearns suffered a massive stroke--and died. The producers had George written out of the series as having gone on a year-long trip the following fall, hence Gale Gordon taking Kearns's place as George's brother John. In Spring 1963, however, the series was canceled, not due to poor ratings, but because its star, Jay North, by this time was 11 years old--henceforth too old to continue playing "Dennis The Menace."

4. Michael Conrad -- OK, so he never was in a sitcom, but Conrad will always be known as Sgt. Phil Esterhaus on the 1980s cop show "Hill Street Blues." In November 1983, just after Thanksgiving that year, Conrad died of cancer at age 58. The producers had his character, Sgt. Phil Esterhaus, also pass away the following spring as having died of a massive heart attack.

5. Richard Crenna -- To sitcom audiences, Crenna will always be remembered as Grandson Luke on the 1950s sitcom "The Real McCoys," but it was while a regular on the CBS courtroom drama "Judging Amy" that Crenna was diagnosed with cancer. He eventually lost the battle against the disease in January 2003, at age 76.

6. Phil Hartman -- Hartman will always be remembered for being the "Man of a Thousand Voices" during his 8 years on "Saturday Night Live," but it was just after Season 3 wrapped of "NewsRadio" in 1998 that, in May of that year, Hartman was tragically shot and killed by his wife, Bryn, who eventually shot and killed herself. The following fall, at the start of NewsRadio's 4th season in September 1998, a special hour-long episode was made to honor Phil's memory by having his character, Bill McNeal, die of a massive heart attack.

Jack Soo (Sgt. Nick Yemana) - Barney Miller

Alice Pearce (Gladys Kravitz #1) - Bewitched

Lynne Thigpen (Ella Mae Farmer) - The District

1. Dolph Sweet from "Gimme a Break!"

2. Redd Foxx from "The Royal Family"

Ward Bond, star of NBC's popular western Wagon Train, died in November 1960, at age 55. Ironically, he was the cover subject on the
then-current issue of TV Guide magazine. He was later replaced by
John McIntire for the rest of the show's run.

Dan Blocker, who played Hoss Cartwright on NBC's long-running Bonanza, died in 1972, at age 43, during that show's 13th season. It only lasted
one more year.

In 1977, Chico and the Man star Freddie Prinze shot himself. The series
expired after one more season.

Marion Lorne (Aunt Clara) - Bewitched

Peter Deuel (Hannibal Heyes) - Alias Smith & Jones

Karl Swenson (Lars Hanson) - Little House on the Prairie

Zara Cully (Mother Jefferson) - The Jeffersons

Will Geer (Grandpa Zeb Walton) - The Waltons

Jim Davis - Jock Ewing on Dallas (died from brain cancer and a perforated ulcer)

Barbara Colby - Julie Erskine on Phyllis (murdered)

Selma Diamond - Selma Hacker on Night Court (lung cancer)

Florence Halop - Florence Kleiner on Night Court (cancer)

Bea Benederet - Kate Bradley on Petticoat Junction (lung cancer)

Jack Soo from "BARNEY MILLER"

William Frawley from "MY THREE SONS" & of course "I LOVE LUCY" and "THE LUCY-DESI COMEDY HOUR"

William Frawley from "MY THREE SONS" & of course "I LOVE LUCY" and "THE LUCY-DESI COMEDY HOUR"

He and Alice Pearce both died on the same day, 03-03-1966

been wondering how did zara cully die i dont think it was ever said

Just FYI, William "Bill" Frawley had to leave My Three Sons because of cost of insurance issues. He was very much alive and revisted the set (off camera). Bill lived a few years past that - but he was not on any series at the time of his death (at least none that I know of).

Just FYI, William "Bill" Frawley had to leave My Three Sons because of cost of insurance issues. He was very much alive and revisted the set (off camera). Bill lived a few years past that - but he was not on any series at the time of his death (at least none that I know of).

Anybody remember when Frawley made a cameo on The Lucy Show? I'm guessing it was after he left My 3 Sons.

Anybody remember when Frawley made a cameo on The Lucy Show? I'm guessing it was after he left My 3 Sons.
I do know that was his last tv appearance and it was after he left MTS.

David Strickland (Suddenly Susan) committed suicide in 1999.

Jerry Orbach-Law & Order although he was on Trial By Jury at the time of his death.

Richard Crenna-Judging Amy

Will Geer from "The Waltons"

A few soap opera people:

Melba Rae (Marge Bergman, Search for Tomorrow)
Theo Goetz (Friedrich 'Papa' Bauer, Guiding Light)
Santos Ortega (Will 'Pa' Hughes, As the World Turns)
Hugh Franklin (Dr. Charles Tyler, All My Children)
Kay Campbell (Kate Martin, All My Children)
Charita Bauer (Bertha 'Bert' Bauer, Guiding Light)
Douglass Watson (Mackenzie 'Mac' Cory, Another World)
Emily McLaughlin (Nurse Jessie Brewer, General Hospital
Macdonald Carey (Dr. Tom Horton, Days of Our Lives)
Frances Heflin (Mona Kane, All My Children)
Michael David Morrison (Caleb Snyder, As the World Turns)
Brent Collins (Wallingford, Another World)
John Beradino (Dr. Steve Hardy, General Hospital)
Norma Connolly (Ruby Anderson, General Hospital)
Josh Ryan Evans (Timmy, Passions)
Mary Stuart (Meta Bauer, Guiding Light)
Anna Lee (Lila Quartermaine, General Hospital)
Ruth Warrick (Phoebe Tyler Wallingford, All My Children)
Benjamin Hendrickson (Hal Munson, As the World Turns)
Eileen Herlie (Myrtle Fargate, All My Children)

Jon-Erik Hexum was fooling around with a .44 Magnum loaded with blanks on the set of the short-lived Cover Up.

He put the gun to his temple and fired not realizing the impact can still be deadly at a close range. He died six days after the incident at 26.

Cover Up went on after his death but was cancelled after one season in 1985.

Seems I am the only one here who remembers Stanley Kammel. He was the wonderful Dr Kroger on the hit series Monk. I was a major fan of that show until Season 7. I still watch it occasionally and my husband is still a huge fan, but without Dr. Kroger it lost a lot of its sparkle for me.

I got some here:

Sidney Clute - Cagney & Lacey during 1985.

Bea Benaderet - Petticoat Junction in 1968. Her death was part of the reason why they changed the lyrics in this show's final 2 seasons.

Phil Carey - One Life to Live this year he died.

Larry Keating, who played Roger Addison on Mister Ed passed away from leukemia on August 26, 1963. Edna Skinner who played his wife Kay Addison left the show shortly after and they were replaced by a new set of neighbors (Gordon and Winnie Kirkwood played by Leon Ames and Florence MacMichael) for the remainder of the series run.

I got some here:

Sidney Clute - Cagney & Lacey during 1985.

Bea Benaderet - Petticoat Junction in 1968. Her death was part of the reason why they changed the lyrics in this show's final 2 seasons.

Phil Carey - One Life to Live this year he died.
Bea Benaderet was already mentioned.

But, yea they changed the line "IT IS RUN BY KATE COME AND BE HER GUEST..." to "IT IS RUN BY JOE COME AND BE HIS GUEST..." and "AND THERE'S UNCLE JOE, HE'S A-MOVIN' MIGHTY SLOW..." became "AND THERE'S A LADY INDEED, SHE'S AS PRETTY AS CAN BE..." (that was a woman doctor who was added to the cast to replace Kate)

Bea Benaderet was already mentioned.

But, yea they changed the line "IT IS RUN BY KATE COME AND BE HER GUEST..." to "IT IS RUN BY JOE COME AND BE HIS GUEST..." and "AND THERE'S UNCLE JOE, HE'S A-MOVIN' MIGHTY SLOW..." became "AND THERE'S A LADY INDEED, SHE'S AS PRETTY AS CAN BE..." (that was a woman doctor who was added to the cast to replace Kate)
I always thought that last line was "And there's a lady M.D., she's as pretty as can be.."

I always thought that last line was "And there's a lady M.D., she's as pretty as can be.."
now that you mention it, I think you're right. I haven't seen the show in years.

Dick Elliott who played Mayor Pike on The Andy Griffith Show died during the series 2nd season and was replaced by Parley Baer as Mayor Stoner

Diana Hyland who played Joan Bradford on Eight is Enough passed away from cancer during the series first season. It was later explained that her character also died and that Tom had remarried.

Glenn Strange who played Sam the Bartender on Gunsmoke died from lung cancer during the series' 18th season in 1973.

I always thought that last line was "And there's a lady M.D., she's as pretty as can be.."

Very close if not right on. I believe it's "Here's a lady M.D..." but you may have it more accurately.

Larry Keating, who played Roger Addison on Mister Ed passed away from leukemia on August 26, 1963. Edna Skinner who played his wife Kay Addison left the show shortly after and they were replaced by a new set of neighbors (Gordon and Winnie Kirkwood played by Leon Ames and Florence MacMichael) for the remainder of the series run.

I read about Larry Keating's death in Alan Young's book, Mister Ed and Me and More!. Young said that Keating pulled him aside and told him he only a few months to live before they starting shooting episodes for the new season. Very sad. :( Skinner was forced to leave the show because they didn't want to replace Keating's character with another actor.

David "Stringbean" Akeman (and his wife) was murdered during the run of Hee Haw, in 1973.

David "Stringbean" Akeman (and his wife) was murdered during the run of Hee Haw, in 1973.

I watched 'City Confidential' one day and they focused on the murder of 'Stringbean' and his wife. It went unsolved for many years until the 1990's when they convicted two men and sent them to life in prison.

Junior Samples and Archie Campbell both died when they were still on Hee Haw.

Here's another Petticoat Junction death that I failed to mention: Smiley Burnette (Charley Pratt) died from leukiema during the break between the 4th and 5th season.

Green Acres - Barbara Pepper (Doris Ziffel) died in 1969 from a heart attack, she was replaced by Fran Ryan for the final two seasons.

I Dream Of Jeannie - Barton MacLane (General Peterson) died in 1969 (during season 4), was replaced by a new character General Schaffer played by Vinton Hayworth.

1. John Ritter -- Perhaps THE saddest of all cases. Ritter, to sitcom viewers, will always be remembered as Jack Tripper on the 1970s sitcom "Three's Company," and as the youngest of 2 sons born to the late cowboy movie actor Tex, but it was while on the set of his comeback vehicle, "8 Simple Rules for Dating My Teenage Daughter," on the afternoon of Thursday, September 11, 2003, that Ritter suddenly fell ill with what he initially thought was food poisoning; instead, at 1 a.m. ET / 10 p.m. PT the next morning, Friday, September 12, 2003, Ritter was dead at age 54. The cause of death -- dissection of the aorta. Ritter's untimely death occurred 5 days before his 55th birthday September 17, 2003; the day after his youngest daughter, Stella, celebrated her 5th birthday; and on the day of his 2nd wife, Amy Yasbeck's, 40th birthday. Besides Amy & Stella, Ritter was survived by 3 grown children (including actor son Jason) from his 1st marriage to Nancy Morgan (which ended in divorce in 1996, in part because of Ritter's relationship with Yasbeck), his mother, Dorothy Fay Southworth (who eventually died the following November 5, 2003 of old age at age 88), and an older brother, Tom, a lawyer who was born disabled by Cerebral Palsy.

2. Nicholas Colasanto -- Although he had a long stage & film career, it was to sitcom viewers that Colasanto will always be remembered as Ernie "Coach" Pantusso on the hit 1980s sitcom "Cheers." On February 8, 1985, after a 2-month absence due to physical illness, Colasanto returned to work on "Cheers," but just 4 days later, on February 12, 1985, Colasanto died of a massive heart attack while watching TV at his California home. The following fall, Coach was written out of the series as also having died, & Woody Harrelson took his place as Woody Boyd, a pen pal of Coach's whom Sam Malone eventually hired to work for him at Cheers.

3. Joseph Kearns -- Although he had a long showbiz career, Joseph Kearns will always be known as Mr. George Wilson on the 1950s sitcom version of "Dennis The Menace." It was on February 17, 1962, hours after the 100th "Dennis" episode was filmed, & ironically 5 days after his 55th birthday on February 12, 1962, that Kearns suffered a massive stroke--and died. The producers had George written out of the series as having gone on a year-long trip the following fall, hence Gale Gordon taking Kearns's place as George's brother John. In Spring 1963, however, the series was canceled, not due to poor ratings, but because its star, Jay North, by this time was 11 years old--henceforth too old to continue playing "Dennis The Menace."

4. Michael Conrad -- OK, so he never was in a sitcom, but Conrad will always be known as Sgt. Phil Esterhaus on the 1980s cop show "Hill Street Blues." In November 1983, just after Thanksgiving that year, Conrad died of cancer at age 58. The producers had his character, Sgt. Phil Esterhaus, also pass away the following spring as having died of a massive heart attack.

5. Richard Crenna -- To sitcom audiences, Crenna will always be remembered as Grandson Luke on the 1950s sitcom "The Real McCoys," but it was while a regular on the CBS courtroom drama "Judging Amy" that Crenna was diagnosed with cancer. He eventually lost the battle against the disease in January 2003, at age 76.

6. Phil Hartman -- Hartman will always be remembered for being the "Man of a Thousand Voices" during his 8 years on "Saturday Night Live," but it was just after Season 3 wrapped of "NewsRadio" in 1998 that, in May of that year, Hartman was tragically shot and killed by his wife, Bryn, who eventually shot and killed herself. The following fall, at the start of NewsRadio's 4th season in September 1998, a special hour-long episode was made to honor Phil's memory by having his character, Bill McNeal, die of a massive heart attack.

I'm kind of surprised that you didn't mention that Richard Crenna also played John Rambo's superior officer, Col. Trutman in the first three First Blood/Rambo films.

Ron Taylor - the guy who did the voice of Bleeding Gums Murphy on The Simpsons.

John Spencer - he died months before The West Wing ended in 2006.

Nora Marlowe - Flossie Brimmer on "The Waltons" died December 31, 1977

Junior Samples and Archie Campbell both died when they were still on Hee Haw.

As did Kenny Price, Slim Pickens, Don Rich and Reverened Grady Nutt

Lynne Thigpen (bka The Chief from Where in the World/Where in Time is Carmen Sandiego?) died while she was on The District. CBS canned the show months after she died.

Madeline Kahn who played Pauline Fox on "Cosby" died during that shows run on December 3, 1999.

Jon-Erik Hexum was fooling around with a .44 Magnum loaded with blanks on the set of the short-lived Cover Up.

He put the gun to his temple and fired not realizing the impact can still be deadly at a close range. He died six days after the incident at 26.

Cover Up went on after his death but was cancelled after one season in 1985.

Jon-Erik was 27.

Deaths before the next birthdate within a calendar year are so absurd, I created a thread about that issue and no one posted in that thread for months.

Jon-Erik was 27.

Deaths before the next birthdate within a calendar year are so absurd, I created a thread about that issue and no one posted in that thread for months.

He was 26 at the time of his death, Deal with it! You seem to have an absurd obsession with celebrities and their age at the time of their passing. Jon-Erik was born on 11-05-57 and died on 10-18-84. Even if he had died at 11:59 PM on Nov, 4th, 1984, His age would still officially be 26.

Zoneboy, that was a mean thing to say. In order to die at age 26 in 1984, one would have to be born in 1958. I have to criticise any pre-birthday deaths in a calendar year too much.

November 1957-October 1984 that's still very, very close to one's 27th birthday. Deal with that!

November 1957-October 1984 that's still very, very close to one's 27th birthday. Deal with that!

Very close but it didn't make the cut. You don't become older until you reach your birthday.

A 20 year old can't buy alcohol even one day short of 21.

Very close but it didn't make the cut. You don't become older until you reach your birthday.

A 20 year old can't buy alcohol even one day short of 21.
That is so true. I don't even consider it my birthday until after 8:20 am on the date I was born.

That was a mean thing to say. In order to die at age 26 in 1984, one would have to be born in 1958. I have to criticise any pre-birthday deaths in a calendar year too much.

November 1957-October 1984 that's still very, very close to one's 27th birthday. Deal with that!
While it is correct to say he was in his 27th year, it is not correct to say he was 27. Sadly he never reached the age of 27 having died BEFORE his birthdate. He was still 26 on the day he died.

Jerry Orbach-Law & Order although he was on Trial By Jury at the time of his death.

Richard Crenna-Judging Amy

I believe Richard Crenna was already listed

Will Geer from "The Waltons"

That was already mentioned

While it is correct to say he was in his 27th year, it is not correct to say he was 27. Sadly he never reached the age of 27 having died BEFORE his birthdate. He was still 26 on the day he died.

I hate death before the birthdate within a calendar year. Now I'm scared o this. I do not want to talk about this anymore since this issue is going to start an argument.

Also, Tim Russert died of a heart complication at age 57 while he was on Meet the Press.

Phil Hartman -- Hartman will always be remembered for being the "Man of a Thousand Voices" during his 8 years on "Saturday Night Live," but it was just after Season 3 wrapped of "NewsRadio" in 1998 that, in May of that year, Hartman was tragically shot and killed by his wife, Bryn, who eventually shot and killed herself. The following fall, at the start of NewsRadio's 4th season in September 1998, a special hour-long episode was made to honor Phil's memory by having his character, Bill McNeal, die of a massive heart attack.

Phil Hartman was also on the Simpsons as well

Ann Sheridan of Pistols 'n' Petticoats died at the age of almost 52 in January 1967. Pistols 'n' Petticoats ran on CBS during the 1966-67 television season.

Mary McCarty - Trapper John, M.D.

She died during that show's 1st or 2nd season, I believe.

Mary McCarty - Trapper John, M.D.

She died during that show's 1st or 2nd season, I believe.

She died at the end of the first season. She was replaced at the start
of the second season by Madge Sinclair as the new head nurse.

This one may not count since it's for a mini-series but I'm mentioning it anyway.

David Dukes died of a heart attack while he was on Stephen King's Rose Red. He died before he was due to come back the next morning to shoot more scenes.

He had appearances in many tv shows and was recurring in The Mommies and Dawson's Creek.

You also forgot Mary Kay Bergman from South Park

You also forgot Mary Kay Bergman from South Park


Who did she do the voices of and when she died?

Who did she do the voices of and when she died?
Mary Kay died 10 years ago today, November 11, 1999. She voiced a number of characters on South Park including Liane Cartman, Sheila Broflovski, and Sharon Marsh.

Werner Stocker died from cancer during Highlander's first season.

Mary Kay died 10 years ago today, November 11, 1999. She voiced a number of characters on South Park including Liane Cartman, Sheila Broflovski, and Sharon Marsh.

Who knew this week would be the 10th Anniversary of her death? This is horrible! :eek:

10 Year's Mary Kay is very Missed

Nancy Marchand who played "Tony Soprano's" mom on The Sopranos.

How did Jack Soo pass away

How did Jack Soo pass away
Jack Soo died of cancer of the esophagus on January 11, 1979.

This one may not count since it's for a mini-series but I'm mentioning it anyway.

David Dukes died of a heart attack while he was on Stephen King's Rose Red. He died before he was due to come back the next morning to shoot more scenes.

He had appearances in many tv shows and was recurring in The Mommies and Dawson's Creek.

He also had a notorious role in tv history as the man who attacked Edith Bunker on her 50th birthday on All in the Family. Less than a year later he played a vicious acquaintance of Jack Tripper's on Three's Company who'd gone blind but was still as vicious as before.

A few soap opera people:

Melba Rae (Marge Bergman, Search for Tomorrow)
Theo Goetz (Friedrich 'Papa' Bauer, Guiding Light)
Santos Ortega (Will 'Pa' Hughes, As the World Turns)
Hugh Franklin (Dr. Charles Tyler, All My Children)
Kay Campbell (Kate Martin, All My Children)
Charita Bauer (Bertha 'Bert' Bauer, Guiding Light)
Douglass Watson (Mackenzie 'Mac' Cory, Another World)
Emily McLaughlin (Nurse Jessie Brewer, General Hospital
Macdonald Carey (Dr. Tom Horton, Days of Our Lives)
Frances Heflin (Mona Kane, All My Children)
Michael David Morrison (Caleb Snyder, As the World Turns)
Brent Collins (Wallingford, Another World)
John Beradino (Dr. Steve Hardy, General Hospital)
Norma Connolly (Ruby Anderson, General Hospital)
Josh Ryan Evans (Timmy, Passions)
Mary Stuart (Meta Bauer, Guiding Light)
Anna Lee (Lila Quartermaine, General Hospital)
Ruth Warrick (Phoebe Tyler Wallingford, All My Children)
Benjamin Hendrickson (Hal Munson, As the World Turns)
Eileen Herlie (Myrtle Fargate, All My Children)
From what I've heard from fans, the death of Douglass Watson was the beginning of the end of AW. I wasn't watching back then (I was still in elementary school and not allowed to watch soaps at that age anyway), but from the many clips I've seen, I can believe that. He really did become the heart and soul of AW, along with Victoria Wyndham (Rachel) and Connie Ford (Ada). Speaking of Connie Ford, we could add her to the list as well, since she too passed away while AW was still on.

I can't belive Jack Soo is going top be gone 31 year's.

Diana Hyland from "Eight is enough"
Larry Riley from "Knots Landing"
Nell Carter from her recurring role on "Reba". She was scheduled to return for some season two episodes but then passed away.

I read about Larry Keating's death in Alan Young's book, Mister Ed and Me and More!. Young said that Keating pulled him aside and told him he only a few months to live before they starting shooting episodes for the new season. Very sad. :( Skinner was forced to leave the show because they didn't want to replace Keating's character with another actor.

That's so sad. Did Young say which episode was Larry's last? I'm understanding the Leo Derocher one was? Do you have any more information on Larry? I'll have to get that book. Thanks for the info!

Colleen Dewhurst passed away in 1991 while playing Murphy Brown's (Candice Bergen) mother, Avery. Colleen won two Emmy Awards for the role. Her death was poignantly written into the series.

Both Johnny Olsen and Rod Roddy died in 1985 and 2003 respectively while Bob Barker was hosting The Price is Right from 1972-2007.

I can't belive Jack Soo is going top be gone 31 year's.

I just loved him on Barney Miller. Really sad he was not on the show longer. Such a funny man.

I have a new one here:

Pete Duel died in December of 1971 while working on Alias Smith and Jones.

Sorry, that too was already mentioned.

Geraldine Carr had a recurring part as Mabel on I Married Joan. She only appears in a handful of third season episodes (Brad and Joan's new house) because she was killed in an auto accident on 2 September, 1954.

If there was a case of a cast member who died after leaving a TV series which was still running at the time of her death, it would be Donna Reed. She replaced Barbara Bel Geddes during the 8th/9th season of Dallas in 1984-85. Reed died in 1988, Dallas ended in 1991.

Actually, Donna Reed passed away in January, 1986, not 1988.

Anybody remember when Frawley made a cameo on The Lucy Show? I'm guessing it was after he left My 3 Sons.

It was after My Three Sons. He left that show during the 1964-65 season, and his one Lucy Show appearance originally aired 10/25/1965, just over four months before he died. I read in one book that Lucy had wanted him for a cameo much earlier, but since Vivian Vance couldn't stand him, Lucy waited until Vivian had left the show to have him on.