Jessica Simpson Tweets Bikini Picture, Debuts Bare Baby Bump

Jessica Simpson is no longer hiding her second pregnancy! 

The mom-to-be tweeted a new photo of herself Sunday, Dec. 30 posing in front of a mirror while wearing a bikini with her bare baby bump in full view.

PHOTOS: Maxwell's baby album

"Bumpin' and proud!" Simpson wrote as the caption. In the shot, the second-time mom-to-be showed off growing belly, and cleavage in a patterned bikini. Simpson, looking makeup free, did wear a matching robe, but kept it open to flaunt her pregnancy.

The proud mama finally confirmed she and fiance Eric Johnson are expecting again on Christmas Day by tweeting a photo of daughter Maxwell, nearly 8 months, sitting on the beach with "Big Sis" written in the sand.

PHOTOS: Ashlee and Jessica through the years

Simpson is currently enjoying a tropical vacation with her family. On Dec. 29, her sister Ashlee Simpson was photographed playing on the beach with son Bronx, 4, and newlyweds CaCee Cobb and Donald Faison.

PHOTOS: Jessica and Eric's whirlwind romance

Johnson, 33, was also seen going for a bike ride with Faison. The NFL pro has been settling into domesticity. "He is amazing with Max," a source told Us Weekly. "Eric tells Jessica he has everything he's ever wanted."

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