Cheryl Fernandez-Versini and Kimberley Walsh celebrate Nicola Roberts' 30th birthday

Cheryl Fernandez-Versini and Kimberley Walsh joined their former Girls Aloud bandmate Nicola Roberts to help celebrate her 30th birthday in style on Sunday night. The trio appeared closer than ever as they partied at the swanky Hotel Chantelle in Mayfair.

The birthday girl stole the show in a black floor-length number boasting a thigh-high split and a sweetheart neckline. Nicola wore her fiery locks swept back in half updo for her milestone birthday.

Cheryl and Kimberley helped Nicola celebrate her 30th birthday on Sunday evening

X Factor judge Cheryl posed up a storm in a black-and-white striped Balmain dress which she teamed with gold Yves Saint Laurent heels.

Kimberley was also stunning in a nude two-piece set, featuring a crop top with accentuated hem, coupled with a two-tone pencil skirt. She accessorised with a pair of black strappy heels and a black leather handbag with chain detail.

The West End star was accompanied by her fiancé - father of her one-year-old son Bobby, Justin Scott, who was handsome in an all-black ensemble.

X Factor judge Cheryl playfully gives her former bandmate a kiss

The couple left baby Bobby at home for the night as they enjoyed the celebrations – and according to Kimberley, it may not be long before the little boy is a big brother.

In an exclusive with HELLO! magazine, Kimberley has revealed her plans to have another baby.

"It would be lovely for him to have a baby brother or sister," Kimberley told HELLO!. "I come from a big family – with two sisters and a brother – and assume that he'd like the same. I used to be adamant about having four children – until I realised that it's not just about me.

Kimberley has revealed plans for the future in an exclusive with HELLO!

"I adore being a mum and can't imagine not having more kids. Motherhood changes you. It makes you softer, more emotional; and you can't believe how obsessed you become by this little person in your life."

The 33-year-old – who will be appearing in the West End stage version of hit comedy film Elf later this month – also opened up about her plans to marry Justin in a romantic ceremony next year.

"I'm very chilled about it," she told HELLO!, who will exclusively cover the happy occasion. "The venue is booked, I have the dress, so the important bits are taken care of. I'm getting very excited – but I'm no Bridezilla."

Read the full interview in this week's HELLO! magazine, on sale now in all good newsagents and available to download on iPad, android, kindle fire and more formats. Or subscribe today to make sure you don't miss an issue!