Britney Spears knows how to have some birthday fun!

The 33-year-old pop star held a joint birthday for her sons, Jayden James and Sean Preston. From the looks on their faces, the trio had a blast at the Skatelab in Simi Valley, California, on Saturday.

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Why a double celebration? The boys' birthdays are just days apart! Jayden James turned 9 on Sept. 8, while Sean Preston will turn 10 on Monday.

The "Toxic" singer even posted a silly selfie with her birthday boys on Instagram. "Happy birthday to my boys," she gushed. "Love you so much Jayden and Preston!" 

Spears also shared pictures of her little skater boys enjoying themselves at the skateboard-themed party, which included a custom made DJ-inspired cake. "Thank you @skatelab and @lindacohencakepops for making this day so special," she wrote.

The boys' father and Spears' ex-husband, Kevin Federline, also attended the party and was very impressed by the sweet treats. "This cake is so dope," he wrote on Instagram.

The fun continued in the car with Spears and her boys having an impromptu dance party on the way home.

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Spears always seems to be having a lot of fun with her sons! Check out the video below of the three re-enacting her Oops…I Did it Again album cover. 

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