She captioned the black-and-white picture, "We are so happy and proud to announce the birth of our ideal daughter, Birdie Mae Johnson".
Earlier this week, a representative for the family told Entertainment Tonight that the star couldn't wait for baby Birdie to be born.
After a hard pregnancy, Jessica Simpson has welcomed her third child.
Simpson broke the news about her pregnancy on Instagram back in September.
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I like to talk about the future because that's what matters. "We're better now and the results have been brilliant". He declined to elaborate, saying only: "Maybe we lost confidence, maybe things went wrong".
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But McQuaid answered with one of his own to start the game-ending run and Xavier Tillman made a tying layup for Michigan State. The two teams must now wait to learn their NCAA Tournament match-ups when they are announced later on this evening.
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Zidane was in the frame to be Manchester United's permanent manager before he confirmed his return to Real. Later, we don't know what the future holds".
The Blast reports that the designer was surrounded by her family during the birth, including her dad, Joe Simpson. "Maxwell, my daughter, is just so happy that it's a girl", she said. "My daughter [already] thinks she's a teenager".
Simpson and Johnson are already parents to their 6-year-old daughter Maxwell Drew and 5-year-old son Ace Knute. "They want to know every detail - like how milk comes out of mommy, how the baby will actually get here and if my belly button is a speaker to communicate with the baby".
She also had to battle insomnia during the end of her pregnancy.
Simpson has been documenting her pregnancy on social media and announced the big news about baby No. 3 late a year ago.
Although we can only imagine the songstress is the most ecstatic of all, considering she carried her third kid through nine long months!