Courtesy of Jessica Simpson
12/30/2012 AT 06:00 PM EST
is celebrating her pregnancy body.
The star, who is expecting her second child
with fiancé Eric Johnson, shared a daring self-portrait of her baby bump on Twitter
Dressed in a bikini and a beach wrap that is hanging open, Simpson, 32, writes "Bumpin' and Proud!" She snapped the picture with a glittery iPhone.
Simpson has been posting lots of photos
while vacationing in Hawaii with Johnson, their 7-month-old daughter, sister Ashlee Simpson
– who flaunted her flat tummy in a barely-there bikini
on the beach – and other family members.
The first picture Jessica shared with fans over this holiday was on Christmas Day: The image of her daughter wearing holiday pajamas and smiling in the sand atop the words, "BIG SIS," confirmed Simpson's pregnancy.