Jessica Simpson Celebrates Birthday With Topless Photo: ‘Kiss My Butt 36’

Jessica Simpson wearing Jessica Simpson Collection hosts a spring style event benefitting The Boys and Girls Clubs of Waco, TX at at Dillard's on May 6, 2017 in Waco, Texas. Credit: Kevin Mazur/Getty Images for Jessica Simpson Collection

Jessica Simpson celebrated her 37th birthday on Monday, July 10, by posting a topless photo that showed off her booty.

“Kiss My Butt 36,” the fashion mogul captioned an Instagram pic that showed her lying in a pool on green floatie.

The singer clutched a drink in a sparkly pineapple as she wore Jennifer Fisher earrings and a thong bikini bottoms that showed off her pert derriere.

Kiss My Butt 36

A post shared by Jessica Simpson (@jessicasimpson) on

The sexy pic came one day after the former Newlyweds star poked fun at her memorable Chicken of the Sea flub.

Simpson shared a photo on Instagram on Sunday, July 9, that showed a photo of a Whole Foods Market with the headline “Whole Foods Discovered Its Chicken Salad Actually Had Tuna.”

The mom of two quipped, “It happens to the best of us @WholeFoods.”

As fans will remember, almost 14 years ago Simpson asked then-husband, Nick Lachey, if the Chicken on the Sea-brand tuna that she was eating during an episode of the MTV reality show was actually chicken or tuna.

"I know it's tuna, but it says chicken by the sea," Simpson said. "Is that stupid?" Lachey shook his head before laughing. "You act like you've never had tuna before. Baby, you and I have had tuna like this before."

The couple split in 2006 after four years of marriage and she went on to marry former NFL star Eric Johnson, with whom she shares two kids, Maxwell, 5, and Ace, 4. Lachey, 43, wed Vanessa Minnillo in 2011 and they are the parents of three children: Camden, 4, Brooklyn, 2, and Phoenix, 6 months.

In an interview published by Complex on Monday, Newlyweds producer Sue Kolinsky said that “you could feel the tension” between Lachey and Simpson during the filming of their hit show.

She added that Simpson really was that naïve when they filmed the series.

"There were times when we were like, 'Hm, does she really not know what this means?'" Kolinsky told Complex. "I truly believe the whole 'chicken and fish' situation was accurate. She really did not know."

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