Ozzy Osbourne may be known as the "Prince of Darkness," but he showed a lighter side recently by visiting patients at Birmingham's Children's Hospital.

The Black Sabbath vocalist has a past with the hospital, explaining to The Mirror, "My son Louis was in Birmingham Children’s Hospital for quite a while as a child and the staff took such good care of him, something which I will always remember."

Osbourne lent his support to the Sunday Mirror's campaign to raise £3.65 million for the hospital's Star Appeal, which will help build a pioneering Rare Disease Center. The Star Appeal's center will provide a single location within the hospital for assessments, diagnosis, treatment, information, research and peer-to-peer support.

“They do amazing work for kids and I’m really pleased to drop in and once again show my support for the Star Appeal – it’ll be a national center that will help families not only in my hometown, but also across the country,” said Osbourne.

During his visit, Ozzy met with a two-year-old boy who is suffering from a rare strand of neuroblastoma who underwent intricate surgeries to remove tumors from his stomach. He also met a 15-year-old boy who suffered kidney failure last year, but recently had a transplant.

To learn more about the Star Appeal's plan, click here.

See What Four Black Sabbath Albums Made the Top 50 Metal Albums of All Time

10 Unforgettable Ozzy Osbourne Moments

More From Loudwire