Sandra Cordero knew her request was unusual.

The mother didn’t walk into the Chelsea Police Department late Sunday morning to report a crime or to fill out a report. She was there hoping that someone would grant her terminally ill son his greatest wish: 2-year-old Edison Cordero wanted to meet a real police officer.

“I need a special favor,’’ she said to Officer Aristides Rodriguez.

“She was very shy about it,’’ Rodriguez said. “She told me [Edison] had terminal cancer and if at least one person could go by and see him. I’ve never had someone ask me that before.’’

It’s been six months since doctors told Cordero that her son had five months to live. They found a brain tumor in May. The family — mom and dad, Edison, and his two siblings — hurriedly moved to Chelsea from Orlando so the toddler could be treated at Boston Children’s Hospital. He turns 3 on Christmas Eve.

For most of his life, Edison has been fascinated by the police, especially their cruisers and sirens. His mother wanted to give him a special experience.

“He was in the hospital for five months,’’ she said in Spanish. “I thought, when I take him out, what should I do to make him happy? He can’t go out much. It occurred to me to pay a visit to the police department. They’re all fathers, sons, brothers.’’

Word quickly spread throughout the department about the little boy’s love of law enforcement. Eight officers, the entire day shift, came together for Edison. Dispatch asked to talk to the him over the radio. Some bought toys and knickknacks for the toddler. Others gathered Chelsea Police Department memorabilia.

“We brought teddy bears, coloring books, whatever we could find around the station, anything that said ‘police’ on it,’’ Rodriguez said. “I gave him one of the patches that goes on our uniform.’’

After lunch Sunday, seven cruisers pulled up single file in front of Edison’s house on Webster Avenue.

The cavalry had arrived.

“I don’t think she expected the whole shift to come down,’’ Chelsea Police Chief Brian Kyes said about Sandra Cordero’s reaction. Building trust with the community is important above all else for the department of 111 men and women.

“If we did something that was perceived to be good, that was yesterday,’’ Kyes said. ­“Today is another day. We’re only as good as each and every shift and interaction.’’

Neighbors peered out of their windows nervously at the line of police cars with their blue lights flashing.

But then the cops exited their vehicles, gift bags in hand.

“It’s nice to show we can pay something forward to people,’’ Officer Richard Rossetti said. “We’re not just there to say, ‘You can’t do this.’ We do have families. We do care about people.’’

The officers waited while, inside the house, Sandra Cordero unhooked her son’s IV.

The boy could see the lights through the window. His mother carried him out into the cold day. Bundled in a coat, a winter beanie with the words “HEROES,’’ and blue-and-green sunglasses, Edison started wriggling in her arms and pointing at the sight of them.

“He was absolutely floored,’’ Sergeant Efrain Gonzalez said. “It was like going to Disneyland for the first time.’’

Edison saw the presents but was determined to explore all the police cruisers, one by one. “Wow,’’ he said. “Wow.’’

Every time Edison pressed a button that caused a siren to blare or a horn to honk, he giggled. The sounds made his mom jump. Then, he’d direct her to another car, where he’d sit inside and play. Once Edison got into a cruiser, he didn’t want to get out.

“Usually [the sirens] scare kids,’’ Gonzalez said. “He was so excited, jumping up and down. It was so good to see my young officers interacting and being a part of something bigger than any of us.’’

In a little voice, Edison blurted “eh-yo’’ (how he pronounces “hello’’) to police dispatch. “Nice to meet you, Edison,’’ a voice promptly replied.

On a day full of domestic calls, this was a few moments of peace.

Gonzalez, who’s been on the force for 30 years, saw it as a career-defining moment. Another officer, Matthew O’Flaherty, had just gotten out of the police academy. It was his first day in the field.

“It was so nice to be unchained just for 30 minutes,’’ Gonzalez said, “to enjoy somebody’s life and family and see the joy you bring as opposed to going on the scene and arresting someone or doing something people see as negative though it’s a necessary part of the job. This revitalized the spirit.’’

After the high-fives and the presents, Edison was happily exhausted. He cried when it was time for the police to go.

The next day, lying in bed surrounded by stuffed animals, a toy police car, and a coloring book called “A Visit to the Police Station,’’ Edison mimicked the sound of the sirens: “Woo, woo, woo.’’

“It was something beautiful that they did for us,’’ Frank Cordero, Edison’s dad, said in Spanish. “I really appreciate them for taking the time. I’ll be thankful for the rest of my life.’’

Cristela Guerra can be reached at cristela.guerra@globe.com. Follow her on Twitter @CristelaGuerra.