Cait's comments have fuelled fan speculation that Kylie has already welcomed her baby

Kylie Jenner is keeping her cards close to her chest when it comes to her rumoured pregnancy.

In fact, fans are convinced that she's already given birth and is just waiting for the right moment to make a big reveal.

And now Caitlyn Jenner has appeared to let the cat out of the bag whilst getting flustered over a question about her grandchildren.

Appearing on Piers Morgan's Life Stories, the former Olympian tripped over her words when asked how many grandkids she has, fuelling speculation that she had to have a quick think about how many she was allowed to reveal.

"I've got 12... 13 grandchildren," she said, which was a mistake.

She actually has 11 - three from daughter Cassandra, one from son Burt, one from son Brandon, three from step-daughter Kourtney Kardashian, two from her sister Kim and one from their brother Rob.

It comes after Khloe Kardashian got seriously awkward when Ellen DeGeneres tried to get the scoop on The Ellen Show last week.

Ellen was asking Khloe if she believes in the 'eating for two' thing, when she snuck in, "Is Kylie craving anything yet?"

Khloe awkwardly laughed and fidgeted with her clothes, replying: "What do you mean?"

"She's pregnant," Ellen insisted.

And Khloe smirked as she said: "Oh, I don't know what you're talking about."

Ellen pushed her further, continuing: "Well why wasn't she on the Christmas card?"

"Umm, I don't know," Khloe replied. "You gotta ask Ky... why don't you get Kylie on the show?"

"Well let's call her, I have a phone right here, what's her number?" Ellen said before jokingly shouting backstage for someone to bring Khloe's phone out.

"But she must be pregnant, I mean there's like too much secrecy around it," the host added.

And when Khloe asked why, Ellen pointed to her face and said, "Look at your eyes, I can tell, y'all she is pregnant, I can tell by her eyes."

"I am pregnant," says Khloe.

And when Ellen said she was talking about Kylie, Khloe repeated: "I am pregnant."

Mirror Online has contacted Kylie's representatives for comment on numerous occasions.