Police cars block the 5800 block of North Patterson Sunday afternoon while officers investigate what they said was a gang-related shooting. View Full Caption Facebook/Joe Basilone

PORTAGE PARK — Jessica Trudeau was just putting her 2-year-old daughter down for an afternoon nap around 1 p.m. when she heard a muffled boom from the second floor of her Portage Park home.

At first, Trudeau didn't think much of it — perhaps her husband, Michael, was fixing something, she thought.

But when she came back downstairs, ready to shoo her 7-year-old daughter outside to play on a beautiful spring afternoon, her front yard had been taken over by nearly a dozen police officers — and a 16-year-old boy lay dead right outside her front door.

"It was surreal," Trudeau said Monday. "It was my worst nightmare."

Giovanni Mathos, 16, died after being shot in his head about 1 p.m. Sunday in the 5800 block of West Patterson Avenue, authorities said.

Trudeau said her older daughter saw Giovanni lying in the street.

"I want to erase that from her mind," Trudeau said.

Heather Cherone says it's a rare shooting for this area:

Giovanni, who lived in the 5500 block of West Henderson Street, about a mile from where he was shot, was walking with two others when a silver or gray car pulled up and people inside began shouting gang slogans, said Officer Jose Estrada, a spokesman for the Chicago Police Department.

Giovanni, a gang member according to police, and his companions shouted back, Estrada said.

A man got out of the car and fired once at Giovanni, striking him in his head. He was pronounced dead at 4:39 p.m. at Illinois Masonic Hospital, according to the Cook County Medical Examiner.

Police said no one is in custody for the shooting, an unusual occurrence during the day in Portage Park, which prides itself on being among the safest neighborhoods in the city.

Trudeau said she and her family were shaken up by the violence right outside their home, where they have lived for 4½ years.

"You never think this is going to happen in your front yard," Trudeau said. "I was trying to remain calm, but I couldn't stop thinking this cannot be real."

The last murder in the Jefferson Park Police District, which covers most of the Far Northwest Side, occurred Nov. 11 when a pizza delivery driver was killed during an apparent robbery, officials said.

It was a "miracle" that no children were outside playing on her block, which is home to nearly a dozen kids, Trudeau said.

"It was such a nice day," Trudeau said. "If it had been 24 hours earlier, my daughter would have been across the street drawing with chalk on the sidewalk."

Everyone in their family had trouble sleeping Sunday night, even with police cars stationed on the street, Trudeau said.

"I kept telling her that we were safe," Trudeau said of her daughter. "I even showed her the police car out front. It was just hard to get those images out of my mind."

Giovanni was one of five people shot to death over the weekend, police said.

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