Tyler was a healthy and active Coweta County high school student, a devout Christian who dreamed of working for NASA.
One day in 2014, he collapsed.
"He was fine all day, then all of a sudden he complained of a headache and started to seize and became unresponsive," Risty said.
It's still a mystery what caused the massive bleeding in his brain that led to his death a week later.
Even though he died, Risty said, Tyler never stopped building a legacy.
"All these kids went to the youth group Wednesday night to celebrate his life, and 30 kids gave their lives to Christ that night," Risty said.
But his mother knew that there were even more ways for her son to not only change lives, but save lives.
"At that point, I decided we need to make him an organ donor," Risty said.
Tyler's organs, bone and tissue went to 23 people across the country, including Lance Frye, who was in desperate need of a new heart.
If it weren't for the organ donation, "I would probably be dead," Frye said.
The 19-year-old Pittsburgh man was born with a congenital heart defect.
"It doesn't just save your life," Frye said. "Now I can do things I couldn't do with the heart I was born with."
Tyler was a student at Northlake High School in Newnan. It's one of the places that Frye saw when he spent time with Tyler's family for Christmas.
"I think it helps to know that this heart came from such a wonderful family and such a wonderful kid," Frye said.
Risty said it's fitting that Tyler's big heart keeps bringing people together, especially on Christmas.
"I think it will bring joy into my home, and that's what Christmas is about -- Christ, and having life after death with him," Risty said.