AceShowbiz -

Kelly Osbourne didn't hesitate to share details of the worst night of her life in her new memoir, "There Is No F***ing Secret: Letters From a Badass B***h". "[One night] Mum had a seizure," she wrote. "I finally called for an ambulance, and together with the idiot nurse, we got Mum stabilized."

Osbourne's mother, Sharon Osbourne, was struggling with cancer during that time in 2002. Her father, former Black Sabbath singer Ozzy Osbourne, wasn't able to handle the situation well. Having abused alcohol and drugs for a long time, things only got worse after his wife was diagnosed with colon cancer.

After finding out about her mother's seizure, Osbourne became afraid. "I had reason to be scared," she wrote. "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."

The family eventually got into the ambulance and was on the way when "dad leaned over and put his hand out and see if Mum was breathing," Osbourne shared. "Then he passed out with his hand over her mouth and it looked like he was trying to kill her."

Having to deal with so many problems at a young age caused the former "Fashion Police" co-host to be addicted to drugs as well. "I had to make phone calls, sign papers, talk to doctors, console family members, and, at nineteen, make adult decisions that would have been hard for someone three times my age," she wrote in her book. "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."

In 2004 and 2009, the British singer entered rehab because of her addiction to painkillers. She also revealed in 2015 that she had cancer gene and might do preventive surgery.

"There Is No F***ing Secret: Letters From a Badass B***h" will be released on April 25.