Say you have two children. One gets to be "normal" and the other one either gay or pornstar, depending on sex where daughter becomes pornstar and son gay.
Naturally you can't choose gay daughter or son pornstar

Both are willing and reasonably happy with their lifestyle in this scenario.
-Pornstar daughter means she does straight sex on film, not anal or facial abuse. She is then not household famous but searchable on the net with a few clips out.
-Gay son is not flamboyantly gay, but open with it when asked and not hiding his orientation to family and friends.
If you choose a gay son the daughter will not go into porn and vice versa.