The Fresh Prince of Bel Air to The Many Loves of Dobie Gillis

Diff'rent Strokes' Arnold and Mr. Drummond considered buying the home of The Fresh Prince of Bel Air's Banks family.

Hello Larry's Larry Alder crossed over onto Diff'rent Strokes for 3 different 2-part episodes

Hello Larry's characters were mentioned on Hi Honey, I'm Home!.

Many Loves of Dobie Gillis' title character crossed over onto Hi Honey, I'm Home!