"I will be at the rehearsals, which is going to very exciting and turnt up! Exactly where everyone wants to be on their 21st birthday... but actually... for me, it is like the best birthday present ever, because I get to perform at the Amas." Miley Cyrus will spend her upcoming 21st birthday on 23 November (13) getting ready for her performance at the American Music Awards, which is set to take place the following day (24Nov13).