Taking to her Instagram page, the former X Factor judge, who is already a grandmother to son Jack’s three children, shared the happy news with her 1.1m followers.
WATCH: Sharon reveals her family has COVID-19
"My [heart emoji] could not be more full!" beamed Sharon. "So excited to share the beautiful journey ahead with you @kellyosbourne."
Sharon’s famous friends and fans were quick to offer their congratulations, with Spice Girl Emma Bunton writing: "Yay!!! Amazing news, so happy for you all."
Former X Factor host Kate Thornton posted: "Congratulations to you, @ozzyosbourne and @kellyosbourne - what a lucky baby to be coming into your care. So thrilled for you [heart emoji]."
One follower told Sharon: "Oh, Happy Day for Kelly & all of your Family! Kelly is going to be such a Great mom ... You set the Bar very high Mrs!"
Another fan wrote: "Awwww yay!!! Congratulations!!! Babies bring so much joy and happiness and I think you all need some smiles after being sick."
Sharon and the entire Osbourne family have recently been unwell with COVID-19, so Kelly’s baby news is undoubtedly a welcome lift for all.
Kelly with her parents Ozzy and Sharon Osbourne
Kelly announced her pregnancy on her Instagram page on Thursday, posting a photo of herself holding up her baby scan, as well as another of her poolside admiring it.
"I know that I have been very quiet these past few months so I thought I would share with you all as to why… I am over the moon to announce that I am going to be a Mumma," she revealed. "To say that I am happy does not quite cut it. I am ecstatic!"
While Kelly has not shared any information on the father, earlier in 2022 she revealed that she was dating Slipknot DJ Sid Wilson, sharing adorable pictures of theirs on Valentine's Day.
"After 23 years of friendship, I can't believe where we have ended up! You are my best friend, my soulmate and I am so deeply in love with you Sidney George Wilson," she wrote.
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