Every time Craig Scott talks about his sister, he's helping to keep her legacy alive.
"She believed in one word really strongly and that was compassion," he said.
At St. Joseph School in Seattle on Wednesday, Craig shared the message his sister Rachel left behind after she was killed in the Columbine High School shooting.
They didn't know Rachel. But it didn't take long for the middle schoolers to be inspired by how she treated others.
"She said I have this theory that if one person would go out of their way to show compassion, it will start a chain reaction of the same. People will never know how far a little kindness can go," said Craig Scott.
Those words inspired what is now known as "Rachel's Challenge" - a program encouraging youth to choose positive influences, dream big and start a chain reaction of kindness.
"Treat each person you ever come across in your life like they matter, like they have value, like they have a story," said Craig.
It's a challenge that students at St. Joe's vowed to take on.
"Craig Scott was a really good speaker. It was a great presentation and I think it moved a lot of people," said student Matt Vredevoogd.
"I don't show my emotions that easily but I really felt it," said Megan Floyd.
And Craig Scott hopes it's a message that will be one that they will never forget.