When 20 school children were shot and killed in Newtown, Conn. last Friday morning, few people in South Florida felt the pain as deeply in her heart as Ady Guzman-DeJesus.

Exactly a month ago, Guzman-DeJesus, just like many of the Connecticut parents, sent her daughter off to school. And hours, later, her daughter, 13, was fatally shot by a young man wielding a gun that had been stored in his mother’s Homestead home.

“I was in the car when I heard about the shootings on the radio,” Guzman-DeJesus recalled. “Everything just came back to me. I began crying and shaking so badly that my friend had to come and help me out of my car.’’

Guzman-DeJesus said she posted some condolences on Sandy Hook Elementary school’s Facebook page.

“I just wanted to tell them that I knew how they felt,’’ she said.

Guzman-DeJesus, in Miami-Dade court Thursday, wept at the memory, as prosecutors agreed to allow her daughter’s shooter, 15-year-old Jordyn Alexander Howe, to be released from juvenile detention where he had been held since the Nov. 20 killing. Howe, who did not appear in court, was ordered to remain on house arrest, monitored by an ankle device, pending his next hearing set for Jan. 23.

Lourdes Guzman-DeJesus, whose nickname was “Jina,” was killed when Howe packed a .40-caliber pistol in his backpack and took it out on the school bus transporting kids to three charter schools in Southwest Miami-Dade. The gun went off, striking Lourdes in the neck. Howe, a student at Somerset Academy Silver Palms, faces charges of manslaughter and carrying a concealed weapon.

The incident happened as the bus was driving children near SW 296 Street and SW 137 Avenue in Homestead. Lourdes, a student at Palm Glades Preparatory Academy, was shot in front of her 7-year-old sister. About seven other students were on the bus when the gun went off, police said.

Prosecutors on Thursday asked the judge for 30 additional days to decide whether to charge Howe as an adult. Judge Richard Hersch agreed to the extension, warning Howe’s public defender that if the teen violated the terms of his release, he would be taken into custody.

Miami-Dade police detectives continue their investigation. After the shooting, they said it appeared that Howe had taken the gun from his parents’ closet and had brought it to school at least once before. The day of the shooting, he was on the bus, showing the gun to another student when it suddenly discharged. Thus far, no charges have been brought against his parents.

Under Florida’s Child Access Prevention Law, it is a felony for a gun owner to leave a firearm where a child can access it, brandish it in public or use it to harm another person.

Gun law expert Jon Gutmacher said that by the time a child is 15, however, they are old enough to know not to bring a gun to school.

“It’s obviously a tragedy. You have a child who takes possession of a highly dangerous instrument. He knows he’s committing a crime and knows it at that age. A weapon doesn’t fire itself. It’s a .40-caliber semi-automatic… and it takes somebody to pull the trigger,’’ said Gutmacher, an NRA firearms trainer and attorney.

However, sources close to the case said Howe had a younger sibling in the home. Gutmacher said if there is a child under the age of 12 in the home, parents should have had the gun locked in a safe.

Howe’s family thus far have declined comment on the case. The gun allegedly was owned by Howe’s stepfather.

“This gun was not in a secure place, there is a younger child in that house, and the parents had the responsibility to keep that gun locked up,’’ said DeJesus family spokesman Ron Book, a lobbyist and child-safety advocate.

“A lot of people are talking around the country today about added laws that ought to be passed,’’ he said.

“But we’ve got laws in place that should have protected this parent and her children and we expect justice to be done and for him to be charged as an adult.’’

Ady Guzman-DeJesus said she believes that God will guide investigators to do the right thing. But, she said, she believes the boy who killed her daughter should be punished.

“He just has to pay,’’ she said.