Jessica Simpson is having a "booty-full" birthday.
The mother-of-two celebrated her 37th on Monday by catching some rays while lying out on a pool toy, and shared a bikini photo to Instagram where she left 36 behind -- literally!
WATCH: Jessica Simpson Rocks Daisy Dukes, Sky-High Heels & Cowgirl Hat to the Beach
"Kiss My Butt 36," she captioned the booty-baring snap.
MORE: Jessica Simpson Hilariously Recalls Her Famous 'Chicken of the Sea' Moment -- Again
Looks like the perfect way to spend a birthday! In fact, the only thing that may top it is the Moana-themed party Simpson threw recently for her 4-year-old son, Ace Knute.
Watch the video below for more.