Don't let 18-year-old Christian Collins' small frame fool you. The 37-inch-tall wise-cracking teen has become a larger-than-life figure on the PGA Tour.
Boo Weekley, Jim Furyk, Rickie Fowler and Aaron Baddeley are his buddies. He texts the world's top-ranked golfer and regularly talks trash to recent Masters winner Bubba Watson over Xbox.
He may be the current king of golf, but Watson stinks at the video game "Call of Duty," according to Christian.
That said, Christian was overwhelmed by excitement, while his brother, Calen, 13, jumped up and down, after getting news of Watson's win at Augusta National Golf Club via a text from Watson.
The brothers have become the face of Caddy For a Cure, a charity that raises money by giving fans like part-time Hilton Head Island resident David Thor a rare opportunity to help call the shots and select the clubs for top-ranked golfers.
Thor spent thousands to carry world No. 1 Luke Donald's clubs during Wednesday's RBC Heritage Pro-Am at Harbour Town Golf Links in Sea Pines. Friend Mario Torchita and Michael Sramek also each contributed thousands to carry Tommy Gainey's and Bill Hass' clubs.
Christian and Calen were born with a rare, genetic bone marrow disorder that often causes birth defects and requires bone marrow transplants. Those with Fanconi anemia also are more susceptible to certain cancers and childhood diseases. About 3,000 have the disorder, according to the Fanconi Anemia Research Fund.
Individuals bid on the chance to caddy for a pro during practice or pro-am rounds at PGA Tour and LPGA events. Proceeds go to the Fanconi Anemia Research Fund and the PGA Tour Caddy Benevolent Fund. Some also goes to Birdies for the Brave, which supports wounded veterans, active military and their families, as well as for a local charity of that tournament's choice.
The Heritage Classic Foundation chose Hilton Head Heroes, which supports families with children who suffer from life-threatening illnesses.
Caddy For a Cure has raised more than $1 million in its 10 years, including about $20,000 through bidding to caddy in Wednesday's pro am, founder Russ Holden said.
"There's really not going to be a cure for Fanconi anemia, but the link with cancer, specifically pediatric cancer, is great," Holden said. "We've made some great strides over the last eight years, where researchers have identified 15 genes through Fanconi anemia research that have been instrumental in breast, prostate, cervical and ovarian cancer" research.
According to Holden, at least one leading expert has said that because of Fanconi anemia research, "we may be on the brink to the answer of (curing) cancer across the board."
Thor, who has been coming to the Heritage since 1984, said he couldn't resist the chance to help the world's reigning golfer and see him work up close, while helping a worthy cause.
So is it nerve-racking caddying for the world's No. 1 golfer?
"Not until the end when I put the bag down in a hazard," Thor said. "Other than that, it was pretty good. ... You get out of their way, stay quiet and occasionally make some comments if it was appropriate. I learned that patience and swing speed is very important. It's like watching an artist."
Gainey said he does his best to "keep it loose" on the course with his caddies in training and relishes the chance to pal around with fans, while directing attention to a seldom-discussed topic.
"These kids and those with FA, they should come first, and that's what we're out here trying to do -- to help them out and make it so they can live a better life," he said.
Christian said he's grateful for guys like Gainey and Donald, "not just because they're famous and can get us a lot of attention, but because they're kind and down-to-earth" and show that the game of golf is much more than jackets and prize money.