Taking a dip in fabulousness! Jessica Simpson flaunted her toned — and out-of-control curvaceous — bikini body while vacationing with her family in Cabo San Lucas, Mexico, on Sunday, January 17.

PHOTOS: The Hottest Bikini Bodies of 2015

The Jessica Simpson Collection founder, 35, worked her slim figure in a cleavage-boosting green bikini by Melissa Odabash, which she teamed with a sheer cover-up, oversized shades, a floral purse and a straw hat. Click here to see more pics of Jessica's amazing bikini body

The mom of Maxwell, 3, and Ace, 2, who she shares with husband Eric Johnson, was visiting the exotic locale in honor of her mom Tina Simpson's 56th birthday on January 18. (Jessica's sister, Ashlee Simpson, and Ashlee's husband, Evan Ross, were also in attendance.)

And from the Instagram photos, Tina had the time of her life! While lounging by the pool, the Simpson sisters' mama, who split from ex-husband Joe Simpson in 2013, got extremely cozy with her sons-in-law, sharing a photo with her legs up in the air and Johnson laying between them.

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