Sharon and Ozzy Osbourne are opening their hearts and wallets to their daughters' best friend -- who lost his mom to the same cancer Sharon is battling.

Robert Marcato's mom, Regan, died last week at 36 of colon cancer. 

Now Ozzy and Sharon will "adopt" Robert, pay for his college education and feature him in the upcoming season of The Osbournes

"He wants to go to drama school, and we're sending him to the best drama school we can find," Sharon Osbourne told The New York Post

"Right now, he wants to stay home in L.A. because he's a bit insecure because he doesn't have any family. 

"We want to get him secure here, then we're going to take our time to pick the best college for him. Robert will be a part of the show as 'Baby Osbourne' -- even though he's 18. 

"We're moving him in as part of the family." 

Marcato has already been featured in several episodes of MTV's hit show, The Osbournes

Sharon bonded very closely with his mother -- and paid for her round-the-clock nursing care during her final days. 

"When I look at somebody like Regan, who didn't have the resources I had, what the [expletive] have I got to complain about?" Sharon said. 

"She was the most amazing woman and was such a brilliant and strong woman. She left home when she was 18, put her baby in the car and drove from one end of the country to another." 

Sharon said she got to know Regan through Robert, who is a friend of Osbourne daughters Kelly and Aimee. 

"The kids had known her for six years and I first met her four years ago," she said. 

"I used to see her at school. I knew Robert through Aimee and Kelly. He became Aimee's friend first, then he went down the line to Kelly," Sharon said, laughing. 

When Regan got sick, Sharon took matters into her own hands. 

"She had no medical care at home and she was beyond saving -- they won't let you stay in the hospital and die, so you go to a hospice or go home," Sharon said. 

"I had private nurses for her 24 hours a day for the last nine days of her life. Every day, the doctors would say, 'Maybe two more hours.' But she lived for nine days -- she defied everybody." 

As for her own cancer battle, Sharon said she's feeling fine. 

"I'm doing OK, I'm fine," she said. "I'm so happy -- three [chemo treatments] down and 22 to go. "I can kick anyone's ass right now!" 

Last season, The Osbournes followed the lives of Sharon, Ozzy, Kelly and son Jack as they moved into a Beverly Hills mansion. Aimee was not part of the show. 

The show became the highest-rated series in MTV history, attracting as many as 10 million viewers per episode. 

The second season kicks off this fall -- and will incorporate Sharon's chemotherapy treatments into the storyline.

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