played the same character when they guested on Love Boat? and I mean besides Charo :lol:

carol channing played julie;s aunt silvia sevreal times

Two more examples:
Ethel Merman - she appeared 5 times as Ros Smith (Gopher's Mom)
Don Most - he appeared at least 4 times as a character named Marv Prine

Pat Crowley played Linda (a love interest for Captain Stubing) a couple of times. :)

I remembered that Betty White was on several times.

I looked her up on IMDb and found that if their listing is accurate, she appeared as "Betsy" on four episodes -- one each from seasons 5, 6, 7, and 9. (I guess she was busy doing other things and missed Season 8!) This was after appearing in a different role once in Season 4 (with Alan Ludden).

Marion Ross recurred as Emily, the Captain's love interest (and eventual wife) in season 9. She was promoted to regular for the final three two hour specials following season 9.

^And then promptly killed off for that one shot CBS Love Boat Valentine Voyage movie....