They're an unlikely pair: a 31-year-old Hollywood actor and his 89-year-old neighbor. But Norma Cook and Chris Salvatore are inseparable.

"She called me the grandson she never had," Salvatore said of Cook. And he considers her a grandmother, whom he describes as “friendly but sassy,” and with a stubborn streak. But recently Cook, who has leukemia, became gravely ill, and spent two months in the hospital battling pneumonia and breathing problems.

Knowing her days are limited, Cook has chosen to spend what time she has left with Salvatore.

"The nurses and doctors told her that it would be a miracle if she lived past the holidays, so the fact that she's still thriving is just a really great thing," Salvatore told TODAY. "She's doing great. If you could see her right now, she looks so cute on the couch with her feet propped up. She just hangs out on my couch and watches TV."

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Chris Salvatore and Norma Cook with Hermes, Cook's beloved cat Gabriel Gastelum

For years the pair lived across the hall from each other in the same apartment complex in West Hollywood, California, but after Cook's hospital stay, doctors told her she couldn't return home to her apartment unless she had 24-hour care, which wasn't covered by her insurance. Salvatore immediately turned to the internet to help, raising more than $50,000 for Cook through a GoFundMe page he set up last Thanksgiving. While they tested caretakers, their GoFundMe savings quickly dwindled, and to cut costs, Salvatore recently invited Cook to move into his apartment.

Salvatore drives with Cook. They have been friends for nearly five years. Courtesy of Chris Salvatore

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"She couldn't be happier that I asked," he said. "I was over there visiting most days anyway."

"The only other option was for her to go into a facility," he continued. "I just couldn't do that to someone who is like my own grandmother."

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Both say the arrangement is working out well, and they've developed a routine.

"He cooks for me," Cook, who is childless and doesn't have close family in California, told TODAY.

"If he can't make it as an actor, he can make it as a chef,” she joked.

The pair on Election Day this past November Courtesy of Chris Salvatore

"We always watch the news," she added. "We mostly talk and drink Champagne and eat peanuts."

Salvatore often posts photos and videos of him and Cook on social media with the hashtag #myneighbornorma. After months of saying hello through their kitchen windows, he knew they would be best friends the first time they met, when he knocked on Cook's door. That was nearly five years ago.

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"She offered me a glass of Champagne — it's her favorite drink — and we just sat down and talked," he said. "We connected right away. Back when she was a young adult, she had a lot of friends who were gay, and I'm also gay, so I think it made her feel safe at home and at peace to sort of have that bond again."

He also took in her cat, Hermes (named after the Greek god, not the fashion house).

The friends celebrated New Year's Eve with Champagne, Cook's favorite drink. Courtesy of Chris Salvatore

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Cook has lived in the apartment complex for about 30 years.

"She does not want to budge," Salvatore said. "My apartment was the only place she would have moved. She has strong opinions about where she wants to carry out the rest of her days, and she wants to stay here."

Salvatore chalks up their relationship to fate.

"Moving her in... it feels as though it was meant to be all along," he said. "It's really fulfilling to be there for her."

And Cook is grateful to have found a true friend in Salvatore: “He’s a really wonderful guy,” she said.