The family found out in November that their youngest son Benny had leukemia, when he woke up on his sixth birthday with a fever.
A few hours later, they were at Children's Hospital receiving the diagnosis.
"It was kind of shocking to wake up on his birthday not feeling well and being diagnosed with leukemia the same day," Betsie said.
After 15 years coaching track and cross country at Carroll, Shawn says he had to stop going to work. He now takes his son to the doctor twice a week and they're waiting for test results to see how his treatment is progressing.
But in the meantime, athletes and alumni are rallying around the family to help.
"I mean Coach T is like a second dad to me," said Abby Carncross, a senior at Carroll on the track team.
She says since learning about Benny's diagnosis, hundreds of alumni have reached out and joined forces with current athletes at the school to raise money for the Thielitz family.