Some people have been claiming that Croix de Fer is a teenager as a way to insult him. I find it highly unlikely that their claim is true. According to his forum profile, he registered in 2011. Unless he were 12 years old or younger at that time, he would not be a teenager now.
There is no reason that he should have to respond to absurd accusations and interrogations and no reason to assume that he is actually under his parents authority.
He didn't deny that he is under his parents authority. But if he is, his parents are not doing a very good job of parenting.
That being said, you're right in that he doesn't have to respond. That's fine. I have to wonder, though, how he treats the women in his family - especially his mother. You will, of course be appalled that I would say such a thing, as you are so often appalled by what I write. But whatever.