Not knowing their separation would be permanent, she had left them behind in the North during the war while fleeing south with her third and youngest daughter.
At the time Ri Sang-chol was just four.
About 132,600 individuals were listed as separated families by the end of July.
But after a rapid diplomatic thaw the North's leader Kim Jong Un and the South's President Moon Jae-in agreed to restart them at their first summit in April in the DMZ. Most of those taking part in the reunions are older than 80, making it likely that this week's heavily supervised get-togethers will be their only reunions.
After the initial tearful reunion was over, Sang Chol showed his mother a photo of her husband, who had been with their son when the couple became separated but has since died. Lee, for example, asked her son how many children he had. She was travelling to meet her younger sisters.
"They don't know what their father looks like so I will tell them what he looked like and when he died", Jang said.
Kim Sun Ok, an 81-year-old North Korean woman, said she found that she and her 88-year-old brother from South Korea resembled each other a great deal. During the whole reunion, they did not let go of each others' hands.More news: As The President Tweets Attacks, Melania Trump Speaks Out Against Cyberbullying
The oldest attendee is a 101-year-old man from the South, who is meeting his North Korean daughter-in-law and granddaughter, Yonhap reported. They're told to avoid saying anything that could be misconstrued, or considered insensitive north of the border.
Participants were applauded by Red Cross workers as they arrived, some in wheelchairs, passing under banners reading "We sincerely congratulate the reunions of the separated families!"
Lee Soo-nam, 76, explains about photos showing his family members during an interview at his home in Seoul, South Korea.
North Korea has shifted to diplomacy in recent months.
President Moon -who himself is part of a divided family - has pressed for increasing the frequency and scale of reunions.
"Oh brother, it will be great when reunification happens", she said.
"It is a shame for both governments in the South and the North that numerous families have passed away without knowing whether or not their lost relatives were alive", he said. "The agony and anger, that's an unthinkable human tragedy".More news: Namibia beats Kenya 53-28 to qualify for Rugby World Cup
Tears were flowing at the emotional reunion between roughly 330 South Koreans, spanning 89 families, and 185 of their long-lost family members from the neighboring North.
"Expanding and accelerating family reunions is a top priority". "The Koreas must more boldly make an effort towards solving the divided families issue", he said. "As a separated family member, I deeply share their sorrow and pitifulness", he said during a meeting with his aides.
But Seoul has failed to persuade Pyongyang to accept its long-standing call for more frequent reunions with more participants. "But he passed so I'll never see him now".
"I'm going to see my nephew and my brother's wife", she added.
"He is very old so I really want to express my gratitude for being alive for a long time". Monday's event included the families of a prisoner of war and five people abducted by North Korean authorities during the conflict - though six South Koreans they had hoped to meet had died.
"My father is all alone here in the South".More news: Official Imaging samples from "the most awaited phone"