The singer's son has been given a cheeky gift

Frankie Sandford has been treated to a super-cute piece of clothing for her unborn son.

The pregnant Saturdays singer – who’s due to give birth this autumn – uploaded an Instagram snap of a tiny top with the words: ‘Lock up your daughters!’ splashed across it yesterday.

‘Got given this yesterday! @rochellethesats @unathesats,’ wrote Frankie, 24.

Band mates Rochelle Humes and Una Healy are, of course, both mums to little girls.

Luckily for Frankie, the pair loved the garment – Rochelle, 24, called it ‘brilliant’ and Una, 31, described it as ‘hilarious’.

But being in the final stages of pregnancy isn’t always fun for Frankie, who’s engaged to footballer Wayne Bridge.

She told her Twitter followers yesterday that she’d just endured an uncomfortable procedure at the doctor’s clinic.

‘I was a big girl today and had an injection without passing out.Haha. Apparently the needle was tiny. I wouldn’t know cos I couldn’t look!’ Tweeted Frankie.

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SEE PICTURES Frankie Sandford and The Saturdays launch the annual Royal British Legion Poppy Appeal

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Anna Duff