Ozzy Osbourne’s daughter Kelly Osbourne has broken her silence days after her father’s death at the age of 76.

News of the pioneering heavy metal singer and Black Sabbath frontman’s death on July 23 was met with an outpouring of condolences from family, friends and fans.

On Thursday, local time, his daughter spoke about her huge loss.

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“I feel unhappy I am so sad,” Kelly, 40, shared on her Instagram account.

“I lost the best friend I ever had.”

Ozzy is survived by his wife, Sharon, and six children — Jessica, Louis and Elliot from his first marriage to Thelma Riley, and Aimee, Kelly and Jack from his second marriage.

Ozzy was spending time with his loved ones just two days before his death.

In a video that was shared to Kelly’s Instagram story on July 20, the late musician could be seen sitting with his daughter and grandson Sidney.

Kelly shares her son with fiancé Sid Wilson.

Speaking to PEOPLE in May, Kelly said her two-year-old son and the rock legend were thick as thieves.

“Oh my God, they’re best friends,” Kelly said of the relationship between her son and her father.

“So, favorite time of the day is night-time because [Sidney] leaves me and gets in bed with my mum and dad because I’m staying in their house right now while my house is getting ready.

“And he goes and gets in bed with them and they have cartoon time together and it is the sweetest thing ever. I have to literally rip him out.”

The Osbourne family announced the rock legend’s passing in a statement to the UK Press Association.

“It is with more sadness than mere words can convey that we have to report that our beloved Ozzy Osbourne has passed away this morning. He was with his family and surrounded by love. We ask everyone to respect our family privacy at this time,” the family said.

Word of Osbourne’s death came more than two weeks after the ailing front man reunited with his original Black Sabbath bandmates Tony Iommi, Geezer Butler and Bill Ward for a triumphant final show on July 5.

Shortly after Osbourne’s death was announced, a two-word tribute appeared on the official Facebook page of Black Sabath: “Ozzy Forever”.

Osbourne had struggled with health issues for years, previously opening up about his battles with Parkinson’s disease and repeat spinal surgeries in a November 2023 interview with Rolling Stone magazine.

“I’m taking it one day at a time, and if I can perform again, I will,” the then 74-year-old singer said.

— With NBC