Jessica Simpson Celebrates Daughter Maxwell's 5th Birthday With a Mermaid Party -- See the Pic!

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Happy birthday, Maxwell!

Jessica Simpson's daughter turned five years old on Monday, and celebrated with the most epic mermaid party!

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"My baby Maxwell is 5 years old today. She makes everyone's life mermaid magical," Simspon captioned a cute family pic -- with Maxi dressed as a mermaid -- on Instagram. "Happy Birthday to our fairytale princess. Mommy, Daddy, and Ace love you with our "holy hearts" (as Max would say) #MerMax #MAXIDREW #canyoube5forever."

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The 36-year-old fashion designer later shared a photo of Maxi's "first splash."

"First Splash #MerMax5 #MAXIDREW," she wrote alongside the sweet baby picture.

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Missing from Maxi's birthday festivities appears to be her "cool" cousin, Bronx. 

See more in the video below.

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