Kelly Osbourne is mourning the loss of her father Ozzy following his death on Tuesday. Osbourne posted a brief message to her Instagram stories on Thursday afternoon. “I feel unhappy I am so sad,” she wrote. “I lost the best friend I ever had.”

Black Sabbath frontman Ozzy Osbourne died following his battle with a genetic form of Parkinson's disease, while a brain expert says the singer's lifestyle could have contributed.

Sharon Osbourne is reportedly considering burying her husband Ozzy in the gardens of their Buckinghamshire estate. The Black Sabbath rocker died aged 76 on Tuesday following a battle with Parkinson’s,

“The moment he walked out on stage, it was just like he was shot with a bolt of lightning and he came alive,” Glendenning recalled. “I didn’t even think it was physically possible for a person that existed day to day the way he did to have that much energy and to turn on that much and to be that much of a showman.”

Kelly Osbourne publicly acknowledged Thursday Ozzy Osbourne’s death with a an emotional tribute. The heavy metal icon, and the face of Black Sabbath, died at 76 “surrounded by love,” it was announced Tuesday.