Surprise! Khloé Kardashian revealed she's having a girl with her boyfriend, Tristan Thompson, on Sunday night's season finale of Keeping Up With the Kardashians — and she seemed disappointed.

The Good American designer's doctor told her little sister, Kylie Jenner — who welcomed daughter Stormi on Feb. 1 with Travis Scott — the sex of the baby, and she delivered the news to Koko, who was visiting San Francisco with Kourtney Kardashian and Kim Kardashian — who welcomed daughter Chicago, via a surrogate on Jan. 15.

"I'm really hoping Kylie's lying," she said on KUWTK, admitting she'd been hoping for a baby boy. On Mar. 4, however, the soon-to-be mama couldn't have sounded more excited. "God gives us what we need! His timing is never wrong! my hormones were IN RARE FORM for that news," she tweeted. "I am now so excited my daughter will have forever best friends with Chicago and Stormi!! God is great!!! Thank you Lord for our princess."

Earlier in the episode, Khloé told her sisters she was "pretty much convinced" she was having a little boy. "I have such anxiety and nerves to find out what I'm having," she said. In October, before Khloé confirmed her pregnancy, People even cited multiple sources who said she was having a baby boy.

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Regardless, the 33-year-old seems ecstatic to be adding a branch to the family tree. When she finally confirmed her pregnancy after months of speculation, she wrote, "Thank you to everyone for the love and positive vibes!" she told her fans via Instagram. "I know we've been keeping this [quiet], but we wanted to enjoy this between our family and close friends as long as we could privately. To enjoy our first precious moments just us. Thank you all for understanding. I am so thankful, excited, nervous, eager, overjoyed, and scared all in one! But it's the best bundle of feelings I've ever felt in my life!" We're so happy for them — and cant wait to meet their little princess!

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