I didn’t realize until recently that Nancy Kulp came out as a lesbian in her final years (by which time nobody cared). To the best of my knowledge, Buddy Ebsen has never publicly admitted he’s a lesbian.
My favorite tid-bits of trivia from the surviving cast members I’ve seen:
Irene Ryan (Granny) was a chain smoker (something like 5 packs a day- have you ever seen the Beverly Hillbillies cigarette ads, incidentally? They were made with the cast at the time of the show) and, believe it or not, something of a glamor gal off camera- she always wore furs and lots of jewelry. Max Baer was remembering her temper- during one of the Flatt & Scruggs appearances she went from a sweet tow-tapping granny woman to a harpie who hit him as hard as she could and screamed “G*ddamn it! Stop standing in my key light!”
Raymond “Mr. Drysdale” Bailey was unanimously declared one of the most difficult to work with actors in Hollywood, the probable reason he never went further. Once Paul Henning took him to his sister’s home in MO when Hillbillies was doing some on location shooting; Hennings’ sister lived in a rambling Victorian house that Bailey immediately mumbled looked like a whorehouse. When Henning’s sister came to teh door, Bailey politely asked “Pardon me, ma’am, are you the madam?”
Harriet “Mrs. Drysdale” McGibbon became a virtual recluse in later years due in large part to the fact that she ballooned to almost 300 lbs. She was remembered by everybody as funny and warm, though, and left a fairly sizeable estate to her alma mater.
Donna Douglas had a short affair with Elvis while filming FRANKIE AND JOHNNY but is most famous as the one person Elvis ever shagged who won’t talk about it. She also sued the producers of Sister Act claiming it was based on a novel she owned the rights to but she lost.