By Caitlin Petreycik
Updated Aug 25, 2011 @ 1:05 pm
Blake Lively
Credit: WireImage; Seth Poppel/Yearbook Library

Happy Birthday, Blake Lively! The Gossip Girl star turns 24 today—she shares a birthday with now-30-year-old Rachel Bilson—and in celebration, we're taking a look back at her transformation from pint-size cutie into red carpet superstar. See Lively's evolution in the gallery!