Jack Osbourne Welcomes Daughter Pearl

Us Weekly --

Welcome to the world, Pearl Osbourne!

Jack Osbourne's fiancee, Lisa Stelly, welcomed the couple's first child -- a daughter -- his rep confirms to Us Weekly.

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Little Pearl weighed a healthy 8 pounds, 6 ounces at birth.

The entire Osbourne family, including Jack's mom, Sharon, and sister, Kelly, have been anxiously awaiting Pearl's arrival, and tell Us Jack will be a terrific father.

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"He's very nervous, but nervous-excited," Sharon, 59, told Us on Thursday. "He'll be a very good dad. I think he'll be very strict, but he'll be a very good dad."

Auntie Kelly can't wait to spoil her niece with the most comprehensive baby wardrobe in town!

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"I already told him that this baby … is going to be the best-dressed baby there is," Kelly 26, has said. "'You're not buying the clothes -- I am!'"

The youngest child of Sharon and Ozzy Osbourne, Jack, 25, announced his engagement to aspiring actress Stelly in September and confirmed her pregnancy two weeks later.

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