By InStyle Staff
Apr 17, 2012 @ 9:15 am
RD/ Kirkland/ Retna Digital; Mike Marsland/WireImage

It's a big day for Hollywood birthdays! Victoria Beckham is celebrating her 38th today, while Jennifer Garner is blowing out 40 candles. In honor of the occasion, take a look back at Jennifer's Hollywood transformation in the gallery, from a dimpled high-schooler to a glamorous mother of three.

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