This Santa Claus maybe laughing on the outside but crying deep down inside—at least during that time when he had an encounter with a terminally ill child.

Eric Schmitt-Matzen, 60, a mechanical engineer and president of Packing Seals & Engineering in Jacksboro, Tennessee, has long been playing the part of Santa Claus to anyone who requests for his appearance. He stands out for the role, looking every bit the Santa Claus that people know about—standing at 6 feet and weighing 310 pounds, according to the Knoxville News Sentinel, which first published his story.

One thing remarkable about him is that, unlike other Santa role players, Schmitt-Matzen's snowy beard is real. He bleaches it regularly to keep its whiteness.

One unspecified day, Schmitt-Matzen said he received a call from a hospital saying there was a very sick 5-year-old boy who wanted to see Santa Claus.

In 15 minutes, he was at the hospital, meeting the boy's mother and other family members. The mother gave him a toy from the TV show PAW Patrol to give to the boy.

He then entered the Intensive Care Unit alone, having instructed the boy's sobbing family members to just stay back.

Schmitt-Matzen sat on the boy's bed and asked, "Say, what's this I hear about you're gonna miss Christmas? There's no way you can miss Christmas! Why, you're my Number One elf!"

The boy looked up and said, "I am?"

"Sure!" Schmitt-Matzen replied, giving him the gift. When the boy saw it, he smiled broadly.

"They say I'm gonna die," he told the man wearing Santa Claus suspenders. "How can I tell when I get to where I'm going?"

"Can you do me a big favour?" Schmitt-Matzen asked, and the boy answered, "Sure!"

"When you get there, you tell 'em you're Santa's Number One elf, and I know they'll let you in," Schmitt-Matzen said, prompting the boy to respond, "They will?"

"Sure!" Schmitt-Matzen assured him.

The boy then hugged Santa and asked his final question, which was actually his final wish: "Santa, can you help me?"

Schmitt-Matzen wrapped his arms around him, and before he could say anything, the boy was gone.

Everyone outside the ICU saw what happened, and they immediately rushed inside, the mother screaming in grief.

Schmitt-Matzen said he handed the boy to his mother and immediately left the hospital, crying "all the way home."

"I was crying so hard, I had a tough time seeing good enough to drive," he told the Knoxville News Sentinel.

Despite his own grief, Schmitt-Matzen had enough strength to work one more show that day.

"When I saw all those children laughing, it brought me back into the fold. It made me realise the role I have to play—for them and for me," he said.