Start of my sixth month, feeling like a tannnkk already! Eek

A photo posted by Bristol Palin (@bsmp2) on Aug 30, 2015 at 11:58am PDT

Three months to go! Bristol Palin took to her blog on Tuesday, Sept. 1, to update fans on her pregnancy and share a photo of her growing baby bump.

In the pic, the 24-year-old second-time mom-to-be cradles her belly as she stands in a spacious grassy clearing with blue skies overhead and a cluster of trees lining the horizon.

"Start of my sixth month, feeling like a tannnkk already! Eek," she captioned the photo, which she also shared via Instagram.

Palin -- already mom to son Tripp, 6, whom she welcomed with ex-fiance Levi Johnston in 2008 -- announced her pregnancy in a blog post back in June, not long after she canceled her Memorial Day weekend wedding to Dakota Meyer.

"I know this has been, and will be, a huge disappointment to my family, to my close friends, and to many of you. But please respect Tripp's and my privacy during this time," she wrote in a talked-about announcement. "I do not want any lectures and I do not want any sympathy." 

Days later, she again took to her blog to address speculation about her baby-to-be. "This pregnancy was actually planned," she clarified. "Everyone knows I wanted more kids, to have a bigger family...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!"

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