Jeremiah Valera was very serious while standing before North Miami Police Chief Larry Juriga, promising “to be kind, helpful and courageous.” It was a special oath written specifically for the 5-year-old, who was sworn in as an officer of the North Miami Police Department for a day.

But for Juriga, it was an emotional moment. “When he said, ‘I do’ and ‘thank you’ after the oath, my heart melted. He is such a tiny boy who has been through so much. It’s amazing to see how strong he really is,” Juriga commented to the Miami Herald.

Valera was diagnosed with stage 4 neuroblastoma more than a year ago and has undergone a litany of procedures, including chemotherapy, two stem cell transplants and radiation therapy, reported the newspaper. While in the hospital last summer, he watched from the window as a parade of law enforcement officers thanked health-care workers.

“He was so excited to see them,” said his mother, Daniela Isaza. Apparently, that was when Valera decided he wanted to be a police officer when he grows up. So, for his birthday this year, Isaza partnered with the Mystic Force Foundation, which contacted the Florida law enforcement agency.

“We wanted to show him how thankful we are for his strength, for his courage for continuing to battle even though things are so hard,” said Juriga.

Valera was provided a uniform shirt with a badge and his name embroidered on it. Instead of regulation handcuffs and a firearm, he was handed Spider-Man web slingers. He was also presented a Spider-Man emblazoned motorcycle, which he took for a test ride with officers from the motorcycle unit. Valera even got to meet the department’s police horses before heading to the Heroes Hangout, a special playroom for children with cancer.

“This really meant the world to us,” his mother told reporters. “To see him happy again is everything.”

Two days after the birthday celebration, Valera checked into the hospital for another round of immunotherapy treatments. Isaza confirmed with the newspaper that her son’s latest scans revealed no evidence of disease (NED). While not technically in remission until he records NED scans for five years, it’s good news for the 5-year-old and his family.