Kris Jenner. Picture: Bang Showbiz

Kris Jenner has seemingly confirmed Khloe Kardashian and Kylie Jenner are both expecting their first child in an Instagram post.

The famous family haven't yet confirmed or denied speculation the two stars are expecting their first children within weeks of one another but the 62-year-old matriarch shared a photo of nine sets of kids' pyjamas on Instagram, revealing there was a pair for each of her grandchildren.

READ: Kris Jenner remains coy on Kylie and Khloe 'pregnancies'

She captioned the picture:

Kris is already grandmother to her daughter Kourtney Kardashian's three kids with ex-partner Scott Disick, Mason, seven, Penelope, five, and two-year-old Reign, her son Rob's 12-month-old daughter Dream, who he has with former fiance Blac Chyna, and Kim Kardashian West and Kanye West's two kids, North, four, and Saint, 23 months.

In addition, Kim and Kanye are expecting their third child via a surrogate, which would bring the total to seven, prompting fans to speculate the two extra sets of nightwear are for the unborn children of Kylie and Travis Scott, and Khloe and Tristan Thompson.

The 'Keeping Up With the Kardashians' stars have stayed tight-lipped on the subject of the pregnancies and 37-year-old Kim recently opted to down a sardine smoothie rather than confirm the news.

During a game of Spill Your Guts or Fill Your Guts, talk show host James, Corden said: "I'm going to give you a sardine smoothie. 

"You love a smoothie. Just think of it as a green juice just with sardines in it. Kim, there have been lots of rumours about your sisters, Khloe and Kylie, being pregnant. Are they true? Yes or no?"

But Kim made the sacrifice and simply picked up the discoloured liquid with foam on top and took a sip, although she swiftly spat it out.

She said: "F**k! The aftertaste. I have to go to dinner after this. So f***ing disgusting."