Will had a shunt implanted in the back of his head to help drain spinal fluid -- a common problem for dwarfs. It hasn't kept him from stepping up to the plate in Little League baseball.
"Every time he goes up to bat, I kind of cringe a little bit," Suzanne Graf said.
"She always says she's really worried I'm going to get hit by a pitch, especially if the kid is really throwing fast," Will said. "But I'm not that scared whenever I'm up."
"To his credit, he stands in there, and he's unflinching," John Graf said.
Both Will and Max relentlessly follow their goals. Gretchen McKay, a reporter for the Pittsburgh Post-Gazette, has chronicled the lives of the brothers since she first learned about them shortly after Max's adoption.
"Max falls down a lot because of his foot," McKay said. "Any time he takes a tumble in the school, somebody immediately comes up beside him and leans down so he can put his hands on their shoulders to get back up."
Will and Max do react differently to things, their parents said. If someone the brothers don't know begins staring at them, Will may choose to simply return the stare.
"I'd just give them a look back, trying to say to them, 'Stop staring,'" he said.
Max, on the other hand, likes to watch the faces of gawkers change when he offers a detailed explanation of dwarfism.
And if being brothers means being competitive with each other, and often annoying each other -- that profile also fits Will and Max.
"We fight like brothers, hang out like friends," Max said.
Will says someday he'd like to run the boutique hotel his parents own. Max is thinking about becoming a journalist. Whatever they choose, they've already settled on the basic principles -- despite coming from opposite sides of the earth.
When asked if anything is more important than brotherhood, they replied, in unison, "No."