The fashion designer and singer paid tribute to America's Got Talent judge Sharon and Black Sabbath frontman Ozzy on microblogging site Twitter as they celebrated their wedding anniversary today.
Kelly wrote: "Happy anniversary mum and dad! you are the definition of true love! 30 years of true love! (sic)."
However, the 26-year-old later corrected herself, observing that her parents are actually marking their 29th wedding anniversary this year.
One Twitter user later suggested that the couple's relationship was not a good one, tweeting Kelly: "Didn't your Dad strangle your Mum unconscious? f****d up love if you ask me (sic)," to which she replied: "Go and f**k yourself with a hedgehog!"
The Osbournes were married in Hawaii on July 4, 1982. Sharon first met Ozzy at the age of 18 and reportedly started dating him after her music mogul father Don Arden dismissed him from Black Sabbath.
Sharon recently revealed she was so shocked to receive sexy text messages from her husband recently that she became convinced that his mobile phone had been stolen. She said: "I got a text from Ozzy yesterday and I'm like, 'Jesus, somebody's stolen his phone.' Because I thought somebody found his phone and they were texting me dirty messages.
"And Silvana, my assistant, goes, 'Oh my god, Ozzy's just sent you this really dirty text.' And I'm like, 'Well it's not him, somebody must have stolen his phone, he can't text'. But it was him."
Two weeks ago, Sharon expressed horror at Arnold Schwarzenegger's cheating scandal, saying: "I was really, really disappointed at [Schwarzenegger] for being so horribly disrespectful and deceitful to do that in your own home. To me, it's just unthinkable."
Watch a fan's tribute video to mark Ozzy and Sharon Osbourne's wedding anniversary below: