pre-gay bio-child
A child that a gay person had with a member of the opposite sex before realizing that he or she was gay.
"Melanie took her daughter Blossom to the park this morning."
"Melanie and Candace adopted a child?"
"No, Blossom is a pre-gay bio-child from Melanie's marriage to Mark a few years ago."
"Melanie and Candace adopted a child?"
"No, Blossom is a pre-gay bio-child from Melanie's marriage to Mark a few years ago."