According to the trusty Internet Movie Database (www.imdb.com), Gabrielle Carteris was born in 1961, and joined the cast of 90210 in 1990, which would have made her 29. 29 plus 13...42? Yikes
Maybe her pregnancy was a way for the writers to slowly write her off the show, being that she was that much older. With a baby, she really didn't have time for the West Beverly/California University shenanigans.
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