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She's here -- safe and sound! "Teen Mom 3" star Mackenzie McKee (nee Douthit) has given birth to her second child. The reality star welcomed a baby girl.

"Welcome to this world baby Jaxie Taylor Mckee. 8.9 19"long," McKee shared via Instagram on Friday. Alongside the caption, the proud mom shared a snapshot of herself and her husband Josh McKee cradling the newborn in a hospital bed.

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One day earlier, the 19-year-old shared the last photo of her baby bump before her little tot's arrival. "Last picture," she wrote via Instagram on Thursday. "37 weeks." In the close-up, Douthit is standing in a hospital room while staring blankly into the camera. She's lifting up her red t-shirt to expose her pregnant belly.

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As Us exclusively confirmed, Douthit and her husband tied the knot last August at The Barn at Timber in Pittsburg, Kansas. The couple is already parents to son Gannon, 2, and with their little boy's help, revealed the sex of baby No. 2 last September.

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"Josh cannot stop smiling. He's always wanted a little princess to look after," Douthit tweeted shortly after the announcement. (The pair cut into a cake to reveal the color pink to their family and friends.) "Now josh is calling all his rodeo friends to tell them #cutedadtweet."

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