Gay people happen. That means that gay children happen, and gay children can be born to anyone or adopted into any family. If someone is not prepared to love a gay child, then what business do they have parenting children at all?
Nobody has any business parenting if they're not prepared for all possibilities. What if the child had been born with phsyical or mental challenges? Most parents would still love their child and provide the best care they possibly can. Yet there are still too many parents that aren't prepared for the possibility of a gay child and subsequently deny adequate care and love. Gay acceptance is at an all time high,but we still have a ways to go.