simon cowell lauren

Simon Cowell's surprising Mother's Day celebration

The Britain's Got Talent judge is having fun

Diane Shipley

Simon Cowell made a rare appearance on social media on Sunday, and it was all part of his unexpected Mother's Day celebration!

The star, who is a doting dad to his seven-year-old son Eric, was pictured on Robbie Williams' wife Ayda Field's Instagram, along with his partner, Lauren Silverman.

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Ayda took her Instagram Stories on Sunday, where she uploaded a snapshot with Lauren.

The two women both looked sun-kissed and happy as they beamed for the camera.

The mum-of-four captioned the picture: "Me and Lauren… getting our mom celebration started. #momsquad."

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WATCH: Simon Cowell enjoys birthday celebrations with son Eric

In her next photo, Simon and Robbie sat together, making fun of their partners!

SEE: Lauren Silverman shows off fabulous figure as she cosies up to Simon Cowell on boat

MORE: Amanda Holden reveals very cheeky 50th birthday surprise from Simon Cowell

They each pouted and Robbie put his arm around his former X Factor colleague's shoulder.

Ayda added the caption: "@robbiewilliams and @simoncowell doing [their] best impression of us," adding a smiley face emoji and the hashtag "bromance".

simon cowell robbie williams

Simon had fun on Mother's Day with Robbie Williams

Neither couples' children could be seen in the photos.

Ayda and Robbie share daughters Teddy, eight, Coco, two, and sons Charlie, six, and one-year-old Beau.

Simon is a father-of-one, while Lauren is also mum to her son Adam, 15, from a previous relationship.

Lauren and her family enjoyed a small get-together in California over the Easter holiday last month, along with Simon's ex-girlfriend (and good pal) Terri Seymour, her boyfriend Clark Mallon, and their daughter Coco.

ayda field lauren

Ayda Field is friends with Simon's partner Lauren

Terri shared a series of snaps of the friends all together, as well as one showing the children sitting at the table near a luxurious home pool.

A small clip showed the three youngsters on an Easter egg hunt, with Eric and Coco sticking very close together.

"Easter love," Terri wrote to accompany the snaps. "Hope everyone had a safe and hoppy Easter!"

In the group shot, Simon was sitting in a dressing gown with the sleeves rolled up, while beaming at Eric. 

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