Character is defined as a feature that distinguishes one person. It's what makes good athletes great. It's what got Sean Karl to UT, and made his story heard all around the world.
Sean was on the tennis court by the time he could tie his own shoes.
"Oh, it was quite a while ago. I'd say probably four or five," Sean remembered.
By 16 years old, he was the number one tennis player in the nation. By his senior year, he was the rated the No. 6 recruit in his class. He had offers from all around the country, but the Nashville-native decided to come to Rocky Top.
"I love the facilities. I love the coaches. I love the guys on the team. I just really felt right."
Sean made plans to graduate high school early, come UT in January and redshirt that first semester. But all of that changed after one trip to the hospital.
"In probably in late August, I was having a ton of pain in my side and went into the doctor. They thought I might have strained something or pulled, which was completely reasonable.
"One day after fall break, I was just in so much pain, that we had to go to the hospital to relieve the pain, and that's where we found out."
Found out that he had cancer. It was a rare form of bone and tissue cancer called Ewing's Sarcoma.
"You know at the time I was in so much pain, and I was on a lot of Morphine and other pain killers. I was mentally numb as well, so it didn't really hit me until a couple weeks later."
Sean's father, Mike Laurie, remembers the moment he got the phone call about Sean's diagnosis.
"You know one day you think everything great. He's down playing tournaments, and literally the next day, I'm at work, and I've learned that he's been diagnosed with cancer. There's no other way to put it other than your whole world gets turned around upside down really quickly."
Within about a week, Sean started his first of several rounds of chemotherapy. What followed the diagnoses, was just as surprising.
He received gifts, letters and mementos from all around the world. He got a signed tennis racquet from Rafael Nadal. Andre Agassi send him a sign book with one message written on the inside cover. He's got his own wristbands and shoe laces. Even a YouTube shout out from one of the sports all time greats- Roger Federer.
"That was pretty awesome. I did not expect it at all. One of the coaches said type this in on YouYube, and I was just like 'alright'. I didn't know why, and then I saw it ,and I thought that was pretty cool.
"You know I didn't expect any of that. I didn't ask for it either. People have just been showing so much support throughout.
Sean will finish his final round of chemotherapy on May 22nd. He graduates high school three days later, and will hopefully have green light to start playing again.
"They've been telling me that once everything's over and all my blood counts get back, that everything should come back pretty quickly."
But at the end of this long journey, what surprised the Karl family the most, wasn't just Sean's character, but the one's around him.
"It's mind boggling, it really is. It makes you realize how wonderful of a world, and how great a community we live in. What wonderful people are here and their support- the daily food deliveries that just keep coming. The people that come over and want to help all the time. Literally, it's overwhelming."