The one that always intrigued me was the Fonz' family tree...How would the tree go by with both the Cunninghams and the Fonz' family line..just curious to find out.

i think most of this was originally compiled by Pat,

CUNNINGHAM FAMILY TREE
Great Great Uncle Hendrick (Joanie's great great uncle mentioned in ep #247 So How Was Your Weekend)
- Sean "Cap" Cunningham (Howard's father - episode #102)
- Grandma Bruner (Marion's Grandmother - episode #5)
- Uncle Leo (Howard mentioned in episode #2 & #88)
- Aunt Bessie (Howard first mentioned in episode #1)
- Uncle Ben (Kelp) (Owner of the Dude-A-Ranch episodes #116, #117, #118, & #131)
- Uncle Joe (Howard's uncle in episode #166)
- Mother Kelp (Marion's mother)
- - George (Howard’s cousin. H&M’s 1st car date in Cousin George’s LaSalle episode 163)
- - Lawrence (Howard's cousin mentioned in episode #47 - Howard's 45th Birthday)
- - Aunt Ceil (Lori Beth's Aunt as mentioned in episode #120)
- - Nancy Blanski (Howard's cousin who introduced H&M - episode #80)
- - Thurman (Richie's uncle who was stampeded by a herd of Buffalo- ep #88)
- - Dick Cunningham (Howard's brother - father of KC in Episode #221)
- - Belle Cunningham (Dick's wife - mother of KC in Episode #221)
- - - KC Cunningham (Howard's niece - His brother Dick's daughter episode #215)
- - Alice Norton (Howard's cousin mentioned in episode #122 Sweet Sixteen)
- - David Allen (Lori Beth's father appeared in Episode #186)
- - Emily Allen (Lori Beth's mother appeared in Episode #186)
- - Howard C. Cunningham (middle initial confirmed by Howard in ep. #155 & #186)
- - Marion K. (Kelp) Cunningham (middle initial from episode #186 R & LBs wedding)
- - - Chuck Cunningham
- - - Richard "Richie" J. Cunningham
- - - Lori Beth (Allen) (Episode when R meets LB and #186)
- - - - Richie Jr. Cunningham
- - - - ? LB was pregnant when Richie comes home from Army
- - - Joanie Louis Arcola (Cunningham) (middle name for Episode #213)
- - - Chachi Arcola (real name Charles Arcola as mentioned in Episode #235)
[This marriage, of course, branches into the Fonzarelli family]
- - - Phillis (AKA Fat Phillis: mentioned as Joanie's cousin in episode #133)
- - - Roger Phillips (Marion's nephew)
- - - Flip Phillips (Roger's brother / real name is Leopold)

THE FONZARELLI FAMILY TREE
- Fonzie and Chachi's grandmother - Grandma Nussbaum
- - Fonzie’s father - Vito
- - Fonzie’s mother - Angela
- - - Arthur Herbert Fonzarelli (AKA the Fonz)
- - - - Danny (the orphan that the Fonz adopts in the last episode)
- - - Fonzie’s brother - Arthur "Artie"
- - Aunt Louisa - Chachi's mom
- - Uncle Gonzo - Louisa's brother
- - Al Delveccio married Louisa to become Chachi's step-dad
- - - Fonzie’s cousins - Spike, Chachi and Angie

that's cool!!

Wow, this is quite an impressive detailed list and a really well documented thread! BRAVO!

There's also Rico Mastorelli (Louisa Arcola/Delvecchio's brother) and his two kids, Mario and Annette.

That is impressive. Thanks for posting it.