Bristol Palin, daughter of Sarah Palin, announced the sex of her second baby on Instagram with a photo of her baby bump captioned, "7.5 months with my baby girl," according to E!. The 24-year-old, who is already a mom to son Tripp, 6, also mentioned the baby's gender in a blog post about birth control over the weekend.

"I know I'm the last to talk about birth control. (Two baby daddies right? LOLZ!) But I am expecting a girl and do have a 14-year-old sister and I would be so concerned for her going into a clinic and having something pretty serious put into her body," she wrote.

The former "Dancing with the Stars" alum announced her second pregnancy in June, after calling off her wedding with Dakota Meyer, as HNGN previously reported.

Palin called her second pregnancy a "huge disappointment" on her blog and faced a lot of criticism for the same. She later clarified that the pregnancy was planned.

"None of us are perfect," she wrote on her blog. "I made a mistake, but it's not the mistake all these giddy a$holes have loved to assume. This pregnancy was actually planned."

"I do not regret this baby. This baby is not a disappointment, and I cannot wait to be a mom times two. Tripp is going to make the best big brother!!" she added.

Palin's baby girl is due in December.