Underwood didn't think of himself as different.
Tragically, the cancer that took his eyesight returned when he was 16, and he passed away.
Underwood's mother shared an inspiring letter to people around the world who were touched by his story. She said: "I pray that each one of us [has] truly taken a piece of this experience, in knowing Ben, and [used] it to become better human beings to one another."
Watch his story here.
Hannah Jewell is a senior staff writer for BuzzFeed News and is based in London.
Contact Hannah Jewell at email@example.com.
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