Shain Gandee's truck
WCHS-TV. Inset: Amy Sussman/Invision/AP
04/05/2013 AT 03:30 PM EDT
Shain Gandee died while "mudding," a passion he displayed while starring on MTV's Buckwild
Gandee's cousin, Ashley Gandee Lewis, 32, describes it as a "country sport" when you "go in clean and come out covered in mud. People make mud holes. They kill up the ground and take the grass off the top. They take a water hose and soak the ground until it gets completely muddy. The more you play, the dirtier you get."
Lewis adds, "As country people, we don't golf. We grab a four-wheeler and some friends and find stuff to do, whether it's rope swinging in the creek or going mudding."
Monday morning was the last time Shain, 21, would ever be seen in his mud-covered Bronco. After missing for 31 hours, the reality star was found unresponsive
in the SUV with two other males, including his uncle.
Lewis – who had seen her cousin two days before his death, when he helped her open Gandee's General Store in Crown City, Ohio – says she and "his whole family said if he was going to die young, at least he died doing what he loved."
Although Shain was last seen at Big Larry's bar around 3 a.m. near his home before he died, Lewis insists his death was unrelated to alcohol.
"From what we know, he was at his girlfriend [Kansas]'s place and wanted to go mudding," she says. "The two other guys agreed to go with him, and his family assumes they got stuck and figured they'd wait until the morning to get out. We think they left the engine running to keep themselves warm and didn't realize the exhaust was covered in mud."
Authorities determined the three males died of carbon monoxide poisoning
after toxic fumes filled their vehicle.
Shain, whose MTV bio page describes him as a "sociable and loyal" family man – is remembered by the network as "a magnetic personality, with a passion for life that touched everyone he met and we will miss him dearly."
On the show, Shain and his costars put their small-town antics on display, creating everything from a swimming pool made out of a garbage truck, to a DIY slip-n-slide. While some uncertainties about his death linger, one thing that is certain is that he will not be forgotten.
"He was a great, well-rounded, respectable young man," Lewis says. "He hugged everyone and shook every hand. He was just wonderful. Buckwild
doesn't show anything normal teens don't do. Shain was raised in church. He didn't back-stab anyone. He was what a real man should be raised like."
The sentiments are echoed by Kanawha County Commissioner Kent Carper, who was always around the Sissonville, W. Va., area where Shain and his pals lived.
"I didn't know him personally, but I know his family very well, and I know all about him," Carper told PEOPLE. "It's not surprising he became the star of the show. He has a big personality. The news is sad and shocking. He was very likable. We live in a very small state. Everybody knows everybody. He was well-respected."
Says Lewis, "I heard Shain's girlfriend hasn't even come out of her room since he died. His family hasn't eaten in days. Everyone is devastated."
Shain's funeral arrangements are being paid for by MTV, while Lewis has established a fund to help raise money for the other two men. On the Facebook page for her general store
, she lists ways to contribute.