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/ Source: TODAY
By Ree Hines

Bristol Palin is already mom to 6-year-old son Tripp, whom she gave birth to just months after her own mother's vice presidential run in 2008. And on Tuesday, the 24-year-old daughter of Sarah Palin revealed whether Tripp has a little brother or a little sister on the way.

It's a girl!

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Palin shared the news in a caption on Instagram, alongside a new photo of her baby bump.

"7.5 months with my baby girl," she wrote.

Palin has kept her followers posted with updates on her growing baby bump throughout her pregnancy.

MORE: Bristol Palin, 5 months pregnant, shows growing baby bump in Instagram selfie

And she often shares photos alongside Tripp.

Palin publicly announced her pregnancy in an emotional blog post in late June, one month after the news that she'd ended her engagement to Medal of Honor recipient Dakota Meyer.

"Life moves on no matter what," she wrote. "So no matter how you feel, you get up, get dressed, show up, and never give up. When life gets tough, there is no other option but to get tougher."

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