A millionaire in California has welcomed a homeless couple into his $4 million mansion to prove that living on the streets isn't "contagious," according to an article by MSN.

The homeless couple was identified as Greg Dunston, a former security guard who got injured on the job, and Marie Mckinzie, a former cashier and certified nurse assistant.

Before Terry McGrath offered them the in-law unit of his mansion in the upper-class Piedmont neighborhood, the couple lived on the streets of Oakland, California for more than a decade.

According to the homeowner, he was touched after reading about their story published in the San Francisco Chronicle last year. They have been living in the estate since February 1, 2019.

Otis Taylor, a journalist for the San Francisco Chronicle, told ABC News, said that when McGrath met Dunston and Mckinzie, he recognized that while they both suffered from disabilities, they "were still engaged with meeting people and they still had love for each other through it all."

According to McGrath, many people have lived in his mansion over the years, including his own children, other relatives and an intern.

However, when the black couple moved in, they faced obstacles as they lived in the neighborhood where the population is almost 72 percent white while only one percent of residents are black, according to data from the US Census.

Some of his neighbors are not happy. McGrath tells of a phone call he recieved.

"I got a call at 9:30 at night on my cellphone -- I thought she was calling about organizing the neighborhood summer block party."

When she mentioned the word 'situation', he thought the neighbor was referencing Marie and Greg. He added, "that was one of the most offensive conversations I've ever had."

There were also several complaints raised with the police, when residents noticed the black couple in the wealthy white area.

"I just pulled into the driveway and there's some strange folks hanging around the house,'' one resident told 911 dispatchers.

Another said: 'I just wanted to notify you that this woman is sitting at Lexford and Hampton ... She's smoking a cigarette -- could be drugs.'

With the numerous complaints, the officers already know how to handle it since McGrath had already coordinated with Piedmont chief of police Jeremy Bowers that Dunston and Mckinzie had moved into his home.

Dunston and Mckinzie said they were happy to leave life on the streets behind.

"I don't want to live on the streets. A lot of people do, but I want to get in," Mckinzie said. "I love to cook a lot so I wanted a kitchen, bed and shower."

"We wanted to do that," Dunston said about moving into McGrath's estate. "There are a lot of people out on the streets but they have no choice."

He added that they "never dreamed or imagined we would be living in Piedmont."

McGrath said Dunston and Mckinzie are now 'family' and that they're welcome to stay in his home for as long as they want.

Meanwhile, BBC News recently reported that there had been some tensions building between the couple and the homeowner one year on from them moving in, as McGrath encouraged them to get paid employment while they sought to volunteer to help others on the streets.

However, it was confirmed that they were only talking about their differences and learning from each other's' experiences.

As California's homelessness crisis continues, acts of kindness like this are crucial. In the entire state, the homeless rate has surged a staggering 16.4 per cent in the past twelve months. This means more than 140,000 California residents are out in the streets without decent shelter which amounts to fifth of the entire homeless population across the US.

In December, California officials announced plans to allocate almost $12 million to clear a mile-long homeless encampment in a popular bike trail housing more than 200 people as it poses a public health emergency after reports of rat-infestation.