Kelly Osbourne recounts her dad's overdose the same night her mom had a seizure in new memoir

Kelly Osbourne has certainly carved a niche for herself in the entertainment world as a successful TV personality, fashion designer and an author -- but growing up as the daughter of Ozzy and Sharon Osbourne, she's gone through a lot to get to where she is.

The 32-year-old star is once again opening up about her childhood in her latest memoir, There Is No F*cking Secret: Letters From a Badass Bitch, which includes some darker moments from her younger life -- such as the time her mom suffered a seizure and her dad overdosed on drugs in the same night in 2002.

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"[One night] Mum had a seizure," Kelly writes in an excerpt from her new book, first published by People, explaining that, after calling for an ambulance, she and a nurse were able to stabilize her mom. However, things only got worse from there.

At the time, Sharon was battling stage-3 colorectal cancer, and Ozzy hadn't been able to cope with the news of her diagnosis. According to Kelly, he went "insane," and began abusing drugs in order to deal with his concern.

So, when Sharon suffered a seizure, Kelly recalled that she "had reason to be scared" of how her dad would react, and it turns out he did exactly what she was worried he would.

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"Dad was there in his boxers, and I watched him scoop his hand into a bowl of pills, swallow a handful of something, and then wash it down with vodka, like it was water and he was dying of thirst," she wrote.

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Not long after, Sharon and Ozzy were both in an ambulance being transported to a local hospital. Kelly wrote that, en route, her dad "leaned over to and put his hand out and see if Mum was breathing. Then he passed out with his hand over her mouth, and it looked like he was trying to kill her."

"I was sobbing and shaking, scared out of my mind," said Kelly, who wrote that, while the EMTs wanted to call the cops on her father, they "took pity" on her because she was so scared and chose not to.

In the years following the frightening incident, her mother recovered from her colorectal cancer, and, in 2012, preemptively underwent a double mastectomy when she was told she was at risk for breast cancer. Ozzy, however, has continued to struggle with drug and alcohol addiction.

The emotional ramifications of that night in 2002 radiated out for years, and Kelly admitted that the incident was the catalyst for her own struggle with pill addiction that would later lead to her going into rehab on multiple occasions.

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"I had to make phone calls, sign papers, talk to doctors, console family members, and, at 19, make adult decisions that would have been hard for someone three times my age," she wrote. "The only way I could even face my life was by opening that pill bottle, shaking out a few pills — or a handful– into my palm, and throwing them down my throat."

Kelly took to Instagram last week to share a candid video of her receiving the first copy of her new book from the publisher, and she couldn't contain her excitement over the culmination of all her hard work.

"I was having the sh**tiest day at work I didn't even have time to take a shower after the gym then I got this surprise that changed everything!!!!!" Kelly captioned the clip.

There Is No F*cking Secret: Letters From a Badass Bitch hits shelves April 25.

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