By InStyle Staff
Mar 27, 2012 @ 11:00 am
Theo Wargo/WireImage; Lionel Hahn / AbacaUSA

What a day for Hollywood birthdays! Mariah Carey turned 42 today, and Fergie blew out 37 candles. Congratulations, ladies! To celebrate, we're taking a look back at Carey's transformation from big-haired high schooler to Grammy-winning glamour girl. Click through the gallery to see her most memorable beauty moments!

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