Four-year-old blind boy navigates curb with his cane for the first time

It's a milestone in the life of brave four-year-old Gavin.

Completely blind, the cute preschooler recently stepped down a curb on his own.

"You can tell he was unsure, yet, he is a lesson in bravery! He has been using his cane independently for a few months now, we have just been working on his steps/curbs/stairs with the cane. He had to talk his way through this, but he did not want any help!" Gavin's parents write on YouTube.

"I didn’t think anything of it, but looking back, hearing him say 'I can do it' is pretty touching. To me, this is something I hear all the time from him, but to capture it on video, when he was very hesitant is pretty cool. My little guy is such a trooper, and is my lesson in bravery, determination and perseverance!" Gavin's mother, Jennifer, writes on her blog, Living with LCA.

"Gavin Robert Stevens was born on Oct. 2, 2008. At 4 months old, we received confirmation of our ever growing worry. Gavin was completely blind. He has Leber's Congenital Amaurosis (LCA), a hereditary retina disease. It is said approximately 3,000 people in the US are affected by LCA," the Facebook group Gavin's Groupies writes.

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Gavin's parents, Troy and Jennifer Stevens, launched the Gavin R. Stevens Foundation to fund the research needed to discover a cure for their brave little boy.

"It's because of our amazing research geneticists, Dr. Chiang, here in America, as well as Beijing, China that Gavin's gene was found. But it will largely be due to our GROUPIES why a cure may in fact happen for our boy! Those who support near and far, and our family who is by our side every step of the way. With God's grace, we are the reason we will be able to make a substantial donation towards this research, that can one day allow Gavin to see things he never has," they write.