Interesting question. I was an actor in an audio recording of her book "Fairest". I met her only once, and she didn't have any family with her. I'm sure if you get in touch with her publisher you could get her contact info.
Gail Carson Levine's birth name is Gail Carson.
Her maiden name was Gail Carson. She has been married to David Levine since 1967. Instead changing her last name, she chose to use both her maiden name and her husband's name.
Gail Rodono's birth name is Gail Cottrell.
Gail Kainswarren's birth name is Gail Kaneswaren.
Gail Borges's birth name is Gail Monast.
Gail Devers's birth name is Yolanda Gail Devers.
Gail Kubik's birth name is Gail Thompson Kubik.
Gail Lynn's birth name is Gail Lynn Kathan.
Gail Emms's birth name is Gail Elizabeth Emms.
David Gail's birth name is David Gilbert Gail.
Max Gail's birth name is Maxwell Trowbridge Gail.
Scanlon Gail's birth name is John Scanlon Gail.