The singer-turned-fashion mogul celebrated her 37th birthday on Monday with a cheeky photo of her in the pool.

“Kiss My Butt 36,” Simpson captioned the topless picture of herself laying on a green floatie.

The mother of two’s pool party comes weeks after she and husband Eric Johnson threw a birthday blowout for their son, Ace Knute, who turned 4 on June 30.

Simpson and Johnson, 37, celebrated with a Moana-themed party — complete with a Maui lookalike — in the family’s backyard, which was made to look like the Isle of Te Fiti, the island of the goddess featured in the Disney film.

In addition, the couple’s daughter, Maxwell Drew, turned 5 on May 1, and marked her big day with a mermaid-themed fifth birthday party.