As parents, it’s never easy to see our child sick, but when a parent hears that their child has cancer, that brings on a whole new level of devastation that most of us can’t even imagine.

Bill Kohler is a medic with the Armed Forces, but he found himself in a situation where he was unable to help his son. Ayden was diagnosed with DIPG, or diffuse intrinsic pontine glioma, a rare form of cancer that affects the brain stem.

He had not one, but two brain tumors and the prognosis was grim. They tried numerous treatments, but nothing seemed to work. So Bill made Ayden a bucket list and they began squeezing in as much as possible in the time he had left.

They met WWE wrestlers face to face, FaceTimed chef Guy Fieri, went hunting, and teamed up with the York Generals semi-professional football team for a fundraiser.

But eventually the time came when Ayden couldn’t walk and he struggled to breath. That’s when he said four words to his dad that Bill will never forget. Ayden said, “Dad, I gotta quit.”

When Ayden was diagnosed, Bill told him to fight as hard as he could until there was no more fight left. When he reached that point, it would be okay to quit. Ayden pushed on and made it seven months and seven days after his diagnosis.

His last request to Bill and his mom, Jennifer, was to gather people around him and sing, dance, and take group pictures. “If anyone asks how I want to be remembered, please say happy, funny, athletic, wise, fighter, caring, and selfless,” said Ayden.

In honor of his son’s life, Bill has continued to fight for a cure for the disease that took his son. They created the 4AydenStrong Foundation that helps children and their families who are experiencing the same things they did.

Bill is pushing lawmakers to fund research for pediatric cancer and answers phone calls at night from parents who are scared and worried for their children. He helps keep them moving forward, regardless of the outcome. He has truly become a rock and is making his son’s legacy live on.

Check out the video below to learn more about Ayden and Bill, but grab a tissue first. Then be sure to share it with your family and friends in honor of Ayden, the happy, funny, athletic, wise, fighter, caring, and selfless kid.