The former X Factor star, 27, kept her blossoming baby bump firmly under wraps in a cape-like bejewelled dress by William Vintage at the Caudwell Children Butterfly Ball on Thursday evening (15 May).
Rebecca announced her third pregnancy in April. She's already mum to kids Lillie May and Karl.
Last night's glitzy event at the Grosnevor Hotel in London raised money for disabled children and their families, and was attended by a string of celebrities including Peter Andre, Gemma Collins, Amy Childs, Emeli Sande and Sam Bailey.
Tweeting afterwards, Rebecca said: "Amazing night and so much money raised for caudwell children , everybody was absolutely lovely."
Singer Rebecca is due to give birth to her third child in November, but she'll be keeping busy until then as she's started work on her third album.
Since finishing runner-up on X Factor's seventh series, which was won by Matt Cardle - she's gone on to enjoy a successful solo career with debut album Heaven - featuring the fab single 'Nothing's Real But Love' – and second album Freedom.
She recently wrapped a tour of the UK and Ireland.
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Celebrities who announced pregnancies in 2014:
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