Whoops! Kim Kardashian West is pretty good about keeping secrets -- but not this time.
The 37-year-old reality star appeared on Wednesday’s episode of The Ellen DeGeneres Show where she let slip that she and husband Kanye West are expecting a baby girl via surrogate.
“My daughter thinks she’s really tricky,” Kim said of her 4-year-old daughter, North West. “We had a baby shower over the weekend, and I thought, ‘You know, I really do want to have a baby shower because I want her to feel that something’s coming and for her to really understand it.’ So people brought toys and gifts and she was opening them all up the next day. She said, ‘Mom, since baby sister’s not here, I think I need all of the toys in my room and I’ll play with them and just make sure they’re all OK for baby sister.’”
When host DeGeneres pointed out to Kim that she had revealed the baby’s gender, the KKW Beauty creator smiled and laughed.
WATCH: Kim Kardashian Gets Candid on Surrogacy Experience -- It's 'So Much Harder'
“North, she’s really excited about that,” Kim said of her and Kanye having a second daughter. “She’s so excited, let’s see if it lasts.”
As for the couple's son, Saint West, who's almost 2 years old, Kim isn’t as sure that he understands that a new sibling is on the way.
“I don’t know if my son gets it yet, especially since I don’t have the belly. It is a different experience,” she admitted. “So I said to my sisters, ‘Would I be really creepy if I just had someone dress up like a big stork and drop the baby off at the front door? And have to explain that? Isn’t that we heard growing up?'”
DeGeneres insisted that it was a weird plan, and also offered up some baby names to Kim, who confessed they she hadn’t chosen one yet and was “freaking out.”
When the daytime host suggested “Lip-Kit West,” Kim quipped, “Kylie would love that.” There was also West West, Pop West, and Star West.
MORE: Kim Kardashian Reveals North Wants to Make YouTube Tutorials -- But Kanye West Isn't Having It
“You know what’s so funny? I’m not going to name her Star, but my daughter picks that name all the time,” Kim said. “I’m not vibing on it.”
Kim recently opened up to ET’s Keltie Knight about welcoming her third child via surrogate, saying, “Anyone who says or thinks it is just the easy way out is completely wrong. I think it’s so much harder to go through it this way.”
Here's more from our exclusive interview: