Alexander Skarsgard's birthday is worth celebrating, but there's room for another celebrity tribute on this 25th day of August - the gorgeous Blake Lively is 23!!

Happy birthday to the Gossip Girl star!

The Los Angeles native has become well-known in recent years thanks to the CW hit, those Traveling Pants movies, Accepted, and The Town, which premieres soon.

In honor of Serena van der Woodsen's real-life, smarter alter ego, click to enlarge the gallery of Blake Lively pictures below and leave a comment on her big day ...