-- After two years of growing his hair, 10-year-old Tyler Boone was finally able to cut it -- as a gift for a family friend, Gabby, who's unable to grow her own.
"She's gone through so much and I think just being a mom and seeing another young kid wanting to help and be a part of something caring and selfless, I think it's very special," Gabby's mom, Emelia Ruiz told ABC News. "She's very quiet and to herself until she gets to know people."
On Dec. 29, Gabby Ruiz, 12, of Riverview, Florida, chopped Tyler's 12-inch locks. The hair will be made into a wig for her to wear.
"She's been comfortable with herself regardless, but she's at that age," Ruiz said. "She's about to be 13 and she wants something different. She's excited to try [the wig]."
When she was 4 years old, Gabby was diagnosed with Alopecia areata--a disorder in which the immune system attacks the hair follicles.
Tyler and his family are originally from Florida where he met Gabby. After playing with Gabby at family parties, he was curious about why she covered her head.
"Tyler asked why Gabby wouldn't take the [cover-up] off her head," Tyler's mom, Denise Boone told ABC News. "We explained that Gabby had a condition that wouldn't let her grow hair."
Tyler decided he'd grow his hair long -- a process that would take two years -- so Gabby could have a wig of her own. "He said, 'Well, it's just hair, I can grow hair,'" Boone said.
While Tyler and his family were home for the holidays, Tyler and his family met Gabby and her mom at Westfield Brandon Mall in Brandon, Florida, so she could finally cut his locks.
After Gabby snipped Tyler's ponytail, the pair posed for some photos at a JCPenney store. Tyler then received a haircut of his choice.
In a few weeks, Gabby will have a new wig made from Tyler's hair by the organization, Children With Hair Loss.
Tyler's parents said they're very proud of their son, what he's done for Gabby and his "super-big heart."
"This is Tyler's personality and it's not something we encouraged him to do," Tyler's dad Jason Boone told ABC News. "They've been friends and Tyler has done some things [for Gabby] as acts of kindness."
Gabby's wig should arrive in about 6 weeks, her mother said.