E/R (1984) to Get Smart (1995)

E/R's Nurse Julie Williams was related to The Jeffersons. And George Jefferson appeared on E/R

The Jeffersons family appeared on the final episode of Fresh Prince where they purchased the house from the Banks family.

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!.

Get Smart (1965)'s Max Smart was mentioned on Hi Honey, I'm Home!

Get Smart (1995)'s Zach Smart was the son of Get Smart (1965)'s Max Smart