Does anyone know why the user MarvelousAlpha got banned?

idk

Well..you should contact one of the Fanpop four and ask them why your brother was banned или better yet,let him ask them.

I don't know

Contact Fanpop! :L
There's a button at the bottom of the page, или Ты can go on Papa's Профиль and message them~

And I don't know, either. Maybe he сказал(-а) something that someone felt was insulting and they reported him или something. или someone was being a troll and reported him for no reason. -.- People are such meanies sometimes...

donno

idk maybe Ты should contact Fanpop if Ты are really so anxious to know, they might be able to help a little.

I'm not sure tbh. I've never even heard of that user before. Perhaps Ты should ask him what he thinks he's done.
Ты might as well contact one of the F4 and ask them to give him his Профиль back. He might be able to get his original Профиль back that way.