Credit: Kristin Cavallari on Instagram Photo: Kristin Cavallari Shows Her Illinois Pride on Instagram

Kristin Cavallari is adding to her brood! The Hills alum recently announced that she’s pregnant with baby number two, and we couldn’t be happier for her and her fiance, NFL quarterback Jay Cutler. That means 15-month-old Camden Jack, the couple’s first child, will soon be getting a little brother or sister!

But how soon are we talking? While Kristin announced her pregnancy on Twitter, she has yet to disclose any details about the due date. "Thank you for all the love!! We are so excited for Camden to be a big brother!" the reality star wrote on Twitter on October 30.

Many moms-to-be wait to announce their pregnancies until they are 12 or more weeks along, so we’re guessing Kristin may be at least in the early part of her second trimester.

MORE: See Kristin Cavallari's Best Maternity Looks

On November 13, Kristin posted this Instagram photo she snapped of herself in black booties, skinny grey jeans, and an Illinois state T-shirt from The Home. T, a company that donates a portion of its proceeds to multiple sclerosis research. Kristin doesn’t say if the pic was taken recently, but if it was, the hot mama is barely showing. (Although we do spy what looks to be a teeny tiny — but noticeable — baby bump!) During her first pregnancy with Camden, the star told Us Weekly that she gained only 25 pounds, so it’s likely that this time will follow suit.

Another unknown is the baby’s gender, although Kristin has indicated that she may be hoping for a girl. But either way, she’ll be more than happy with the outcome. “...I would love to have a little girl,” she told Us in September, “but if I had another boy, that would be great too."

Source: Twitter, Instagram, Us Weekly, Us Weekly