Aug. 14, 2014 at 9:36 AM ET
On a mission trip with Operation Smile in Panama, 13-year-old Zachary Lori is all smiles.
But it hasn't always been that way.
He and his two younger brothers were born with a rare condition called facial paralysis.
WATCH: ‘Three Little Bears’ helps comfort kids facing surgery
"They couldn't close their mouth when they were born," Zachary’s mom Lisa Lori told TODAY. “They had difficulty with eating and swallowing and speech."
They also couldn't show any facial expression and couldn't smile.
After dozens of doctors told them there was no hope, the family found Dr. Ronald Zuker, a pediatric plastic surgeon.
Dubbed the smile doctor, Dr. Zuker volunteers for Operation Smile, an international medical charity that provides free reconstructive surgeries for children with cleft lips and pallets.
"Organizations like operation smile are incredibly important to these people who otherwise would have no option to have this surgery, " Dr. Zucker said. "It's a real blessing for us to be able to provide this to them."
He also pioneered a muscle transplant surgery that he hoped would help the Lori boys.
"This was the first time that we had done this operation for this condition," he said. "It was always a bit of a question as to how well it would work."
After a total of 8 surgeries, one at a time, the boys recovered and came out smiling.
"It was gorgeous," Lisa Lori said. "The emotional impact of having a smile - to be able to communicate, to go to school, to one day get a job and to have a normal happy life — I don't know what we would have done without it. It's really changed our life."
The family was so thankful for their new lease on life, they wanted to give back, so they created the Three Little Bears — Zachary, Luke and Griffin.
When children go into surgery they are allowed to bring one item for comfort and in developing countries, kids often don't have anything to hold.
Now when children have an Operation Smile surgery, they can bring a teddy bear that represents a little boy who understands their pain.
"If they just hug the bear really tightly, they don't get scared," Griffin, 10, told TODAY.
During a recent mission, Zachary was able to go with his parents to hand out teddy bears and give a little extra comfort to kids who, like him, are learning to smile for the first time.
"We've taken something that was challenging and negative in their life and really turned it into a positive," Lisa said.
Sometimes the best medicine is lending a hand to others.