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Ke$ha turns 25 on March 1, 2012. The singer is most notable for her single 'Tik Tok,' which sold over 600,000 digital copies in one week, making it the most downloaded song in a one-week period by a female artist. She Tweeted this video to her fans on her birthday, saying: 'I love you guys so much!' (pictured above).
( Photo / twitter.com/keshasuxx/status/175291227493761024)