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The "Sorority Row" star was spotted celebrating the milestone on Saturday night at TAO at the Venetian in Las Vegas.
Rumer was joined by her famous family at her birthday soiree including her mom, Demi Moore, and stepfather Ashton Kutcher; dad Bruce Willis and stepmother Emma Heming; and younger sisters Tallulah, 18, and Scout, 15. The not-yet-legal girls stayed for dinner and left before the rest headed up to the club.
And Rumer celebrated with not one, but two cakes – including one delivered on the dance floor by an Elvis impersonator.
The star was also joined by boyfriend Micah Alberti, "Sorority Row" co-star Audrina Patridge – who brought ex-boyfriend Corey Bohan – and Holly Madison, among others.
The partygoers closed out the night with the help of a bottle of Cristal delivered by another impersonator, one copying Madonna – who shares a birthday with Rumer. The Material Girl turns 51 today.
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