Teen Battling Rare Cancer Sworn In as Honorary Detective: 'It Was a Great Day'

Sean Dixon, a 16-year-old bravely battling a rare bone cancer, had the best day of his young life while serving as an honorary detective in a suburban New York police department.

The high school junior was diagnosed with osteosarcoma, an aggressive cancer that has already claimed his right leg, when he was just 14.

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He is currently in treatment for a series of growing tumors.

His grandfather was a cop in Long Island's Nassau County, and Dixon has long been enthralled by passed-down tales of police work and protecting citizens.

For his 16th birthday, Dixon was invited to join the neighboring county of Suffolk’s police department. This week, he was sworn in as detective for a day, and he could not stop smiling even though he was supposed to be catching pretend bad guys.

On an outing with the K9 unit, the boy was coached on what to say before sending in a four-legged officer to corner a suspect.

“I know you’re in there,” Dixon called out, doing his best to sound stern. “Come out and show me your hands.”

He also hung out with homicide investigators, sat with a 911 dispatcher to monitor emergency calls and was given a department ID card and a badge.

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“They made a dream become a reality," he told ABC News. "It was something I’ll never forget."

The day’s activities wore out the teenager, who uses crutches to get around since his leg was amputated at the hip.

But his mother, Kim Dixon, said her son’s energy never lags in fighting the disease that has spread to his lungs and his brain.

“It’s getting worse, but it does not stop him,” she said.

He even has a girlfriend, she said.

As he left the department Tuesday, employees lined the building's entrance, clapping as he walked past.

“It was a lot of fun,” the boy said. “It was a great day.”

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