The music mogul sent the affectionate greeting to Cheryl via Twitter earlier today after it was officially confirmed they will both be back on this year's X Factor judging panel.
He tweeted at her: "Welcome back to my favourite lil brat."
Simon and Cheryl are known for their playful frenemy antics, stemming from Chezza being sacked on US X Factor a few years ago after just a few days in the job.
She's since said it took plenty of grovelling on Simon's part for her to forgive him and rejoin X Factor in the UK last year! Now, she's on her fifth year on the show overall and no doubt hoping to beat Simon this year after he won last series with Ben Haenow.
Cheryl may have competition to be Simon's favourite brat now that newcomer Rita Ora has joined the show!
It was confirmed today that 'RIP' singer Rita and her close friend Nick Grimshaw, who hosts BBC Radio 1 Breakfast Show, will replace Mel B and Louis Walsh on the panel.
Caroline Flack and Olly Murs will replace Dermot O'Leary as show hosts, while Sarah-Jane Crawford's replacement on Xtra Factor has not been named.
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