Jack Osbourne welcomes daughter Pearl

Jack Osbourne has become a father for the first time; his fiancée gave birth to a girl called Pearl.

Jack Osbourne and Lisa Stelly have welcomed baby Pearl / Copyright WENN

Lisa Stelly was due on April 18, but little Pearl was fashionably late as she arrived on Tuesday 24 April weighing in at 8lb 6oz.

The new parents have kept quiet on Twitter so far, but Jack Osbourne retweeted Hello! magazine's confirmation of the baby's name and weight.

Jack's sister Kelly Osbourne thanked her Twitter followers for their congratulations last night, tweeting: "I am one proud Auntie!"

[Related article: Jack Osbourne is going to be a father as well as a husband!]

Ozzy Osbourne and Sharon Osbourne now have a grandchild in their brilliantly bonkers family.

Sharon Osbourne was already planning on indulging the baby before she arrived, telling People: "I'm going to be the grandmother from hell because I am going to spoil this baby so bad.

"My son and Lisa are going to be like, 'Get her out of here!'"

Jack Osbourne and Lisa Stelly are parents to Pearl / Copyright WENN

Late last night, Sharon Osbourne tweeted: "Today I witnessed my first grandchild being born, life changing experience. She is an angel."

Jack Osbourne and Lisa Stelly announced their engagement at the end of September, and then less than two weeks later they revealed they were expecting their first child.

The dad-to-be admitted he was "excited [and] a little nervous" about his impending role as a father.

Congrats to Lisa and the Osbournes!