Kim's secret nod to 'pregnant' sisters Khloe and Kylie

Only one of the three Kardashian sisters that are said to be 'pregnant' at the moment have confirmed their bun-in-the-oven status.

But did Kim just drop a huge hint at their matching baby-on-board situations?

In a post shared to her 103million Instagram followers last month, Kanye West's wife shared an image with her sisters Khloe and Kylie on vacation.

Simply captioned, 'The three of us...' fans are now speculating it was an affectionate in-joke between the siblings.

Last week news of Kylie's rumoured pregnancy with her new beau, Travis Scott, broke quickly followed by suggestions elder sister Khloe too was pregnant with her man, Tristan Thompson.

Kim has been the only one to confirm she is set to become a mum again, revealing her third baby which she was having via a surrogate, was on the way in a trailer for the new season of Keeping Up With The Kardashians.

The pregnancy news is particularly exciting for Khloe, 33, who has spoken openly in the past about her wish to become a mum.

Kylie, 20, has only been dating her rapper boyfriend for a few months.

Kardashian fans who are desperate for the triple pregnancies to be confirmed have been leaving comments on the cryptic snap, begging Kim to spill the tea.

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"Look Kim spilled the beans! 'The 3 of us,'" one user commented on the snap of the trio in Costa Rico, while another said "Omfg the caption, such a hint."

Wonder how long they'll leave us all hanging before confirming the pitter-patter of tiny Kardashian feet?

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