jack Osbourne Names Newborn Baby Girl Pearl

Jack Osbourne has officially become a father to a baby girl. HELLO! Magazine has just broken the news that the 26-year-old son of rock legend Ozzy Osbourne and his fiancee Lisa Stelly have welcomed their first child together, and they named their bundle of joy Pearl.

"HELLO! can exclusively announce the safe arrival of @MrJackO & @lisamarstelly 's baby girl Pearl weighing 8lb 6oz," so wrote the magazine's editor Rosie Nixon on her Twitter page. "Love & congrats to them!" The tweet has since been retweeted by both Jack and his older sister Kelly Osbourne.

Jack announced that he's expecting his first child back in mid-October 2011, less than two weeks after announcing his engagement to Lisa. His baby was actually due to arrive last Wednesday, April 18, but on Friday, April 20, Lisa tweeted, "Still pregnant :( apparently I made too lovely of a home in there! #overit #comeonbaby."

While Jack hasn't come out with official statement regarding the arrival of his daughter, his sister Kelly has taken to her Twitter to thank fans for the congratulatory messages. She tweeted, "thank you so much for your congratulations but they realy (sic) should be gonig (sic) to @lisamarstelly & @mrjacko! I am one proud Auntie!"