Death can be bittersweet. For a family of faith, it is a time of celebration and sorrow. In Ennis, hundreds of people packed into a funeral home for Symon Castillo.

The 22-year-old tragically lost his life after a night out with friends and family in Fort Worth. The family tells WFAA that he had a flair for style and was always very giving for people who needed help.

Family also tells WFAA that people mistook him for someone much older. But he lived up to it by deciding at age 18 to be an organ donor.

"He said I'm doing it. I'm gonna do it," said Timpestt Castillo.

"He was gonna be somebody's hero," said sister Tatum Gallardo.

But nobody ever thought he would be the hero to his own father, Nate Castillo. He had been battling diabetes for 20 years, and just in the last few years decided to get serious about living healthy. His doctors told him it was too late and that his kidneys were failing.

"Just the mention of dialysis scared me," said Nate Castillo. He badly needed a donor. His son's untimely death had opened the door for Nate to have one of his son's healthy kidneys. When WFAA had met with Nate, he was on a hospital bed at Baylor Hospital in downtown Dallas.

"I don't even know how to explain the feelings that are there," he said.

The last time father and son were together was on a field playing softball. That would also be the last time they talked. "We played ball Wednesday night. I actually got to say 'I love you!'" a father said.

Father and son bonded already by blood and baseball, now bonded in a way no parent wishes.

"I'm actually jealous. He has a part of him," said Emma Castillo, his mother.

Nate was discharged from Baylor Hospital just hours before his son's funeral in Ennis on Wednesday.

"I didn't think he would be saving me instead of burying me," he said.

So far, there have been no complications from the transplant. The journey toward recovery is expected to be a long one.

"I think that gives us all a little peace knowing, he's still living," said Timpestt.

Nate says he may not play softball ever again. His body can survive it, but his heart cannot.