Appearing on The Talk on Monday, Mrs O sat down to talk to Mel B and Vanessa Feltz via a virtual interview.
Sharon admitted that everyone was in tears after Kelly broke the news to them, and Ozzy Osbourne was the first to cry.
VIDEO: Sharon Osbourne opens up about being fired from The Talk
Asked how Kelly told them her news, Sharon explained: "She did it over the phone! She was away, she was with her guy, and she called us and told her 'I've got something to tell you,' and I was a bit like 'Oh no, what is it now?' But it was great news.
"We all cried. Her dad was the first one to cry. It's just a blessing. It's a real blessing."
Sharon added: "We are so excited. It's just great news."
Sharon Osboune reveals Ozzy Osbourne was the first to cry following Kelly Osbourne's baby news
When asked how Kelly was doing, she replied: "She's doing great! Now she's further along it's a real reality for her and she's really over the moon."
The Osbournes star is already a doting grandmother to three young granddaughters from her son Jack Osbourne, who is also expecting another baby.
Kelly Osbourne is expecting her first baby
She said: "Going to end up with five. I don't think it's the end, it's just the beginning I think." On what kind of a grandmother she is,
Sharon added: "I just think what goes on at Grandma's, stays at Grandma's. I just have the kids and I spoil them rotten, and then they go back to dad and I tell them - don't say a word!" Kelly announced her baby news on Thursday in a sweet Instagram post, showing her posing alongside a baby scan.
The star wrote: "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.
Jack Osbourne is also having another baby
"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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