The story starts in 1981 when Grandpa and Grandma picked up the Xiong family — Hmong refugees with a passel of skinny, dark-eyed children — at the Eau Claire, Wis., airport.

Well, actually the story starts before that, during the Vietnam War, when Hmong living in the mountains of Laos were recruited by the CIA to fight the communists, using spy techniques and guerrilla warfare.

In 1975, when the Americans pulled out, the Hmong were left to the mercy of the communists. Genocide began immediately, with thousands of Hmong killed and entire villages wiped out by “yellow rain.” Hundreds of families trekked across the Laos countryside and swam the Me­kong River to refugee camps in Thailand.

Grandpa and Grandma, with the backing of their local congregation and a sponsor program headed by the Lutheran church, offered an empty house and enough support to put a refugee family on their feet. When they met the Xiongs at the airport that day in 1981, they soon discovered that Gi, the oldest son, was the only one of the family who spoke English.

Gi said he was 18, but Grandpa said later he thought he couldn’t possibly be more than 16. A hardworking farmer himself, Grandpa soon found him a job at the local cheese factory. Gi didn’t last more than a few days before the boss told him not to come back.

“I was so undernourished, I couldn’t work,” Gi told Grandpa many years later. The family had lived like deer in the Laos countryside, eating leaves from the trees until they reached the refu­gee camp. Gi’s muscles had been so weak, he couldn’t do much, and he fell asleep at his work.

Grandpa hadn’t known.

The Xiongs stayed in my grandparents’ house only six or eight weeks before they asked to be taken to St. Paul, Minn., about three hours away, where their married daughter lived. About a month after dropping them off, Grandpa and Grandma drove back to St. Paul to see how they were doing. The Xiongs had disappeared, with no one in the house where they had been but a man who said he’d never seen them.

They heard nothing until years later, when Yer — the tiny 14-year-old who’d spent happy hours playing with their daughter who was just her age — wrote to thank them. She was still in St. Paul, now a successful realtor, and hoped to stay in touch. She took my grandparents out to eat, and Grandma began sending her a Christmas letter every year. Yer wasn’t a letter writer, but sometimes she would send a card.

A second surprise contact came when Grandma needed knee surgery. She and Grandpa chose a skilled orthopedic surgeon an hour’s drive from their home.

On their first visit, the surgeon, Nathaniel Stewart, asked their names and then informed them that his wife, Yer, was their little Hmong refugee. He offered them the knee surgery at half price.

Dr. Stewart, a kind man who got right down to the level of his patients, seemed to take a liking to my grandparents, and a bond of friendship grew between them. I think he admired Grandpa’s determination, his gruff and kind-hearted character. I know Grandpa thought highly of him.

Sometime later, Grandpa reconnected with Gi, who had become a prosperous business owner in California. The Xiong parents had passed on, but their children were doing well for themselves.

In the years that followed, Dr. Steward aided my grandparents substantially with other medical emergencies — finding means for them to cover the costs they would not have been able to handle on their own.

And that’s how a good deed done in 1981 leapt 30 years and repaid my grandparents with more than they had given.

Lucinda J. Miller lives in Boston. She is the author of Anything But Simple: My Life as a Mennonite and blogs at lucindajmiller.com.