There aren't any official RPG's however there are hundreds of ones set up by fans, try Proboards, InvisionFree, Chamber of Chat and Zetaboards.
Well there's Pottermore for a start.
There are many Harry Potter RPGS (virtual games) out there. All you need to do is preform a search.
Yes, there are many Harry Potter RPG's online.
Any Virtual Worlds For Teenagers Were You Can Be A Fairy
No Harry Potter doesn't have any sibling's.
Yes there are.
No
Harry Potter does not have any brothers or sisters.
Azeroth
there is Be Bratz
Tinier Me
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