By Leigh Martinez

MODESTO (CBS13) — A teenager’s sudden death at school has parents searching for answers about his last minutes.

Andy Vasquez, 16, collapsed and later died following a gym class earlier this week at Gregori High School.

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His family says he he loved to play around and make his sisters laugh. But the fun-loving teen had a serious heart defect and had open-heart surgery two years ago. He recovered well enough to take PE at school.

“He had no restrictions,” said his older sister Stephanie Vasquez. “His doctor allowed him to do everything except football.”

But on Tuesday, after running two miles around the field and bleachers, Vasquez collapsed in the weight room. His sister says a teacher and administrator made several calls to Vasquez’s father asking if Vasquez had any health conditions.

“My father father got very upset,” she said. “My dad told them in Andy’s freshman year that he had this heart procedure. That they’d have to keep a close eye on him and they agreed. They agreed.”

The school called Vasquez’s sister and parents to the weight room, but they weren’t allowed inside.

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“His principal came out and said ‘Expect for the worst,’” she said.

Vasquez’s family says they don’t’ know when the school called for medical help, but were told it was the principal who performed CPR.

“His principal told me when he got there, my brother was breathing slowly. As he was trying to bring him up, he tried to find his pulse, but there was no pulse,” she said.

The school couldn’t find a written policy on how to handle student health issues on campus and had no further comment.

His sister says Vasquez didn’t show signs of sickness this past year and wonders if the school did enough to save her brother.

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“We honestly don’t know anything,” she said. “We’re still looking for answers.”