‘Then she did it.’ Mom who murdered her two children left note before suicide

Unhappy about her former husband’s attempt to leave her once and for all, Nisleydis Sierra penned a note to him, placed her two young children in her bed and picked up a gun.

“Then she did it,” a law-enforcement source told the Miami Herald.

Sierra shot and killed the kids. Then she pointed the weapon at herself and pulled the trigger, the final act of violence in a shocking double-murder suicide in South Miami-Dade.

Sierra was 29. Law-enforcement sources on Monday identified the dead children as 18-month-old Alfredo Hernandez-Sierra, and 8-year-old Amberly Hernandez-Sierra.

The double-murder suicide on Friday afternoon ended what had been a rocky relationship since the couple divorced in 2011, court records show. Legal squabbles over child support dragged on for years.

In 2013, Alfredo Hernandez testified in court that he lost his job in the banking industry and was now selling life and health insurance. That year, he was ordered to pay $227.24 a month in child support.

Florida’s Department of Revenue reported in January that it had stopped overseeing child-support payments. If the court records are accurate, the child that bears his father’s name was born almost five years after the couple’s marriage fell apart.

Hernandez, who neighbors said was questioned at length in a police vehicle after the bodies were found, couldn’t be reached although he is not considered a suspect. A note was left at his last available address, though neighbors said he appeared to live at the home at 25389 SW 132nd Ave., where the killings took place.

A woman at Sierra’s family transport business said “no comment” when reached by a reporter.

“The father of the children came home and found his two kids and ex-wife deceased from gunshot wounds,” Miami-Dade police spokesman Detective Argemis Colome said Friday.

According to police and witnesses, Hernandez visited the beige single-story home in a relatively new subdivision of South Miami-Dade, not far from Homestead-Miami Speedway, just past noon Friday and found his ex-wife and two children already dead.

He called police.

Neighbor Harry Dye — who said he was friendly with the family — said he got home just in time to see Hernandez placed in a patrol car. He said it was about 1 p.m.

“There was no expression on his face. He looked right at me. The police said it was shock,” Dye said.

Dye, who has lived next door to the family for about 18 months, said Hernandez had moved back in with the family about four months ago. He recalled conversations about the couple going to a counselor, but from all appearances, all was well, Dye said.

“They’re beautiful people. I don’t know what took place. I never heard them argue,” he said.

He said Hernandez had recently bought a small boat and talked about taking his family to Black Point Marina. He said Sierra always walked Amberly to school and doted on her children.

A knock on the family’s door Monday went unanswered. Sierra’s white Chevrolet Equinox SUV sat in the driveway. A statue of two angels that said “welcome” rested on a small table on the front porch of the home.

Alfredo Hernandez “was there all the time,” said Dye’s partner Martin Dye. “I didn’t see anything strange at all. They were very friendly. When we saw what happened, we were just in shock.”

This story was originally published September 25, 2017 at 3:06 PM with the headline "‘Then she did it.’ Mom who murdered her two children left note before suicide."