JoBeth Williams was 36 in Poltergeist II: The Other Side when she played the character 'Diane Freeling'.
That was over 38 years ago in 1986.
Today she is 75, and has starred in 67 movies in total, 51 of those since Poltergeist II: The Other Side was released.
In Poltergeist II: The Other Side, I think JoBeth Williams looks: