Aaron Carter Good Genes or Good Docs?

6/22/2009 2:22 PM PDT

Aaron Carter: Good Genes or Good Docs?

Famous for being Backstreet Boy Nick Carter's kid brother, Aaron Carter is now a grown man.

Here's the 12-year-old back in 2000 (left) -- and nine years later, the 21-year-old version in Toronto this weekend (right).

It's amazing what not having your music or acting career takeoff can do for a guy.