Una Healy is dating rugby player Ben Foden

Frankie Sandford has been measuring Una Healy's growing baby bump - and she's uploaded the evidence on to Twitter.

The Saturdays star Frankie, 22, who's just returned to the group after a mystery illness forced her to take a break, is delighted with her bandmates's changing body.

'I've been very impatient for Unas bump to show. I've come back and it's finally here! The Sats baby is growing!!!!! :),' she's Tweeted, alongside a picture of her measuring Una's tummy.  

Una, 30, is due to give birth in March to her first child with rugby player boyfriend Ben Foden, 26.

'My baby gave me an almighty kick for the first time today that it made me jump! That's my ab workout for the day! :),' she's Tweeted.

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Esme Riley