There are holes in Amy Schisler heart that will never heal after she lost her son Tanner this spring.

"If you've ever watched a toddler topple and you gasp to catch it. That's the way I feel. But I can't catch him. He's already been caught," Schisler said.

Her son was 20 years old when he collapsed at the Ace Miller Memorial Boxing Tournament in February.

"It's like being without part of your heart. It's like gasping for breath and not being able to catch your breath," she said.

He was an honors aerospace engineering student with a 3.9 GPA. His mom says he wanted to go to Mars.

And on Friday, with a deep breath and holding back tears, his mom walked the stage and accepted his diploma on his behalf.

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