EastEnders star, 41, took to Instagram on Sunday to announce she and her husband Phil Davies had welcomed their bundle of job.
Sharing an adorable photo of her little one, the star - who played Carly Wicks on the BBC soap between 2006 and 2008 - let her following know the big news.
She wrote: 'So there’s this new fella in my life…. and wow! #babyboy. 'Kellie and Phil already share twins Pearl and Louis, seven.
Kellie turned her newborn twins into lifesavers by donating their umbilical cords to people with blood cancer, she recently announced.
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