The family of Marvin Knutson continue to mourn his tragic death in Great Falls, Montana earlier this week.

The 72-year old was killed in a hit-and-run when a semi tractor-trailer made an illegal maneuver, sending him off the road while on his way back home from a winter in Mesa, Arizona.

One of Marvin's grandchildren, Stefani Erdahl, who lives in Vancouver, Washington, shares the feelings being expressed by the family since learning of his death.

"Absolute heartbreak, horror, devastation - all those sorts of feelings. It's not a normal situation (hit-and-run); not anything anyone expects to experience, especially when it's your grandpa."

Knutson has been recognized by members of the community for his selfless work within the city of Swift Current, which Erdahl and family have witnessed first-hand.

"I'm pretty sure the whole city would agree that he was known for his generous heart," she said. "He helped one of his employees buy a house, he donated clothing, and he sent my Grandma out to buy clothes for his staff in the winter if they were struggling. I used to be jealous because he'd give different kids in the neighbourhood presents for Christmas who were in need - he was a really wonderful person."

For Erdahl and the rest of Marvin's extended family, what may be missed most is his positive outlook on life.

"My Grandpa had a wonderful sense of humour. He made pretty much everything that came out of his mouth into a joke. He just had a really wonderful way of life and it was always with a smile on his face."

No new developments have been discovered in the investigation by Montana Highway Patrol. As updates do arise, look to Swift Current Online.