Durham, N.C. — An 89-year-old man and his 85-year-old wife who were missing for more than 27 hours over the weekend were found safe Sunday night.

A Silver Alert was issued around 2:30 a.m. Sunday for Willie Bias McLeod and Evelyn Louise McLeod, who had last been seen leaving their home on Independence Avenue in a silver Chevrolet Impala.

Around 6 p.m. Sunday, a woman and her husband called authorities about an Impala weaving down the road in Mocksville, about two hours west of Durham.

The woman managed to get the couple to pull over and stayed with them until state troopers arrived. Troopers ran the car's license plate and learned that it matched that of the McLeods' car.

The couple's son, Walter McLeod, said Monday that his parents are showing early signs of dementia and that the family has been working out living arrangements for the couple of 63 years.

The Impala, he said, is now being kept at a relative's house.

According to Walter McLeod, his father told him that the couple was going to do some work for Willie McLeod's mother, who died decades ago.

The younger McLeod said the family is relieved and elated that they were found safe.

"It is extremely tough to think about what might have happened to them," Walter McLeod said. "I'm thankful it turned out the way it did."

Developed in 2007, the Silver Alert system quickly notifies the public about missing endangered people who suffer from dementia or other cognitive impairments.