Jerry Mathers (star of "Leave it to Beaver") appears with other former child actors in the special feature on Family Affair season 4 dvd. He says he played Cissy's date, but they don't show a clip or give the title.

What is the name of the episode of "Family Affair" in which Jerry appeared?
It's not listed on imdb and I can't find his name in any episode guides.

I also find it odd that they never showed a clip of him from the episode, but they showed clips of the other kid actors on the panel.

This is a very good question. I'm sorry I haven't been able to find an answer.

One thing that lends credence to what Jerry says about having been on is that he did appear on My Three Sons later on -- and both M3S and Family Affair were Don Fedderson productions, with connections between the two as far as common actors.