Popa saying that another poster is a member of his family is not what I would consider believable (so if it was true, I wouldn’t say so).
If you look here, you’ll see that he’s been registered for six years, so he’s probably a lot older than 16, especially judging
by how he wrote when he started out:
theyeshivaworld.com/coffeeroom/profile/popa_bar_abba