Ozzy Osbourne's wife/manager Sharon Osbourne became a first-time grandmother this past Tuesday, April 24 when their 26-year-old son Jack and his fiancée, actress Lisa Stelly, welcomed a daughter named Pearl at a healthy 8 lbs., 6 oz.Ozzy already had four grandchildren; two each from daughter Jessica and son Louis from his previous marriage to Thelma Riley. It is the first child for Osbourne and Lisa Stelly, who gushed about her future husband when announcing their engagement. At the time, Sharon said, "I'm happy because it's what Jack wants, so I'm happy. And I've always wanted to be a grandma, so it couldn't be better." Jack's sister Kelly tweeted on Tuesday, "thank you so much for your congratulations but they realy should be gonig to @lisamarstelly & @mrjacko! I am one proud Auntie!" Added Sharon: "Today I witnessed my first grandchild being born, life changing experience. She is an angel." Jack found fame through his family's MTV reality show "The Osbournes" and has since appeared in several other TV programs. Last year he produced a documentary about his father called "God Bless Ozzy Osbourne".