If you suspect your child is gay why not trust them and ask?Could it be that parents know but just don't want to acknowledge it?
I asked my daughter.She admits to swinging in both directions.However we have yet to inform her father or anyone else in the family.I suggested that a former Royal Naval Charge Chief that has a hatred for gays developed by the old attitudes engendered by that institution needs to be approached carefully and with many dropped hints along the way.
My son tells me he is most definitely not gay and judging by some of the 'literature' in his room I believe him.He just doesn't like the representatives of the female gender that he is aquainted with at school thus far which is why he is avoiding the dating ordeal that so many of his age have to stumble through.
So I say again if you want to know ask.Unless you are scared of the answer.
As for the older man gay or otherwise chatting to my daughter or son I don't mind.Not everyone is a paedophile after all.It's when my daughter wanted to meet anyone that I panicked and insisted on going with her.
My son has thus far shown no real interest in chat rooms until this year when his PC broke and he had nothing to do but visit Xbox forums on my PC.If he wants to meet someone I will no doubt go with him just to check.
Incog.