In the snap, the singer flashes her butt and black panties while the former NFL player stands in front of her while holding a pint of beer in each hand.
“38 IS GREAT 🍻#IAMSOHOTFORYOU” Simpson captioned the flirty pic.
Reactions to the provocative post were mixed — with some users sharing their distaste.
“Girl, there's a time and place for everything but... ‘Oh no Baby what is you doing?!’” commented one follower.
While another added: “Highly inappropriate. Should be behind closed doors.”
This is not the first time The Dukes of Hazzard actress has celebrated a birthday with a cheeky snap on Instagram. The songstress, who turned 37 in July, rang in her special day by sharing a revealing Instagram pic. In the photo, a topless Simpson lies flat across a green pool float while showing off her booty in a colorful bikini.
“Kiss My Butt 36,” she captioned the pic at the time.
Simpson and Johnson, who got engaged in 2010 after four years of dating, tied the knot in a private ceremony at San Ysidro Ranch in Santa Barbara, California, in July 2014.
In May, the fashion designer opened to Extra about her husband, whom she calls her “guilty pleasure.”
“We do do dates, but it’s more like couch dates, make-out dates,” she revealed. “He always loves me and I don’t know how… Maybe because we got really amazing kids. He always just takes care of me.”
The happy couple, who are parents of Maxwell Drew, 5, and Ace, 4, celebrated their seven-year wedding anniversary in May by sharing a sweet black-and-white snap of the family.
"7 years, 2 kids, and a whole lotta love later," she captioned the Instagram post.
And while the picture-perfect foursome have a lot of fun together, the couple isn’t rushing into having more children anytime soon. In an appearance on the Ellen DeGeneres Show in May, Simpson told the 59-year-old host: “We got an IUD, nothing is gonna get in that uterus,” she said jokingly. "I have two beautiful children and I'm not having a third, they're too cute — you can't top that.”
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