"With light assistance, he is walking pretty much on his own," Brezenski said. "It’s still unsteady, but since last year it’s vastly improved."

With his speech largely unfazed since coming out of a medically-induced coma that lasted over a month, the biggest issue still facing Greenwood is his short-term memory, which has improved, but not as significantly as his physical abilities.

"If I have a conversation with Brett, he would probably be able to have a decent conversation, it’s just trying to remember things and what happened five minutes before, 10 minutes before," Brezenski said "That’s the thing that tends to cause a lot of people a lot of problems with this specific type of anoxic brain injury he has, so that’s something he’s going to be working on for the years to come."

Still, given a negative prognosis initially by doctors, the strides are nothing short of incredible.

"I think each day he’s grateful where he’s come so far from (since) the day of the injury to about three years (later) now," Brezenski said. "Having a brain injury, I think he would tell you, and anyone who’s suffered a brain injury and going through the rehabilitation process, it’s a struggle on a daily basis."

That's what makes days like his birthday so special.