I was looking at the actor info at IMDB and it said the "Joannie" and Betty Buckley were both born in 1947. I know that the mother was a "younger" remarriage for the dad, but still, isn't that a little close? It's not unusual for a 30 year old actress to play a teenager, but I just thought this was strange.

By the way, the original mother (who died) was born in 1936. So even she was not that much older than some of the actors playing the kids.

Yeah, the ages were close in real-life, but Abby was supposed to be in her mid-to-late 30s and Joannie was supposed to be around 20 at the beginning, so the on-screen age difference made sense. It was just that Betty Buckley was playing a character about 7 or 8 years older than she was in real life, and Laurie Walters was playing a character about 10 years younger than she was in real life (similar to Gabrielle Carteris on "90210").

Even though they were the same age, Buckley had a much more mature look than Walters, so I think it worked out OK.

I think "Joannie" looked very young for her age, if she truly was 30 when the show started.