Neighbors were not sure how long Pedro Alberto Monterroso-Navas, his five children and girlfriend had been in the country, only that they had been in Metairie for a few weeks and lived a quiet, hardscrabble life while there.

Their apartment had spartan furnishings — one mattress, a night stand and a TV — and the power apparently went out at times.

Among the five children, the oldest, a 12-year-old girl, seemed to act as a mother for her siblings, doing things such as cooking for them.

Heidi Monroy, the 24-year-old girlfriend believed to have been the mother of at least three of the children, spent most of her time talking on her cellphone, while Monterroso claimed to spend most of his time working, neighbors said. What, exactly, he did was unknown.

What led to a violent outburst that ended with Monroy dead in the bathtub early Sunday morning also remained a mystery on Monday to those who live in the 4000 block of Durand Street.

After the death, Monterroso fled Louisiana with three of the children, while two he apparently had with Monroy were left behind. Police issued an Amber Alert and began a manhunt for the suspect in the death of Monroy.

Monterroso and his children were found late Sunday or early Monday morning in a trailer park near Katy, Texas, a Houston suburb.

Monterroso, 43, was taken to the Harris County jail to be held on a count of second-degree murder.

The children — his 12-year-old daughter, a 4-year-old son and a 2-year-old son — were in the custody of Texas authorities, the Jefferson Parish Sheriff’s Office said.

It was not immediately clear where the two children, ages 8 and 5, who had been left in Metairie were on Monday.

Neighbors said they thought a relative or family friend might have taken custody of them after Monroy was found dead. The Sheriff’s Office referred questions about the children to the state Department of Children and Family Services, which did not respond to a request for comment.

Col. John Fortunato, a Sheriff’s Office spokesman, said investigators were led to Monterroso when one of his children called a friend who also was in Katy.

The mother of that child called authorities to provide them with information about the location of Monterroso and the children.

A Harris County Sheriff’s Office spokeswoman said Monday afternoon that details about where and when Monterroso, an undocumented immigrant from Honduras, was taken into custody were not immediately available because he was still being processed into the jail.

It was not immediately known whether Monroy was in the country legally.

Immigrations and Customs Enforcement officials did not respond to questions about Monroy or about what action Monterroso might face from federal authorities.

Neighbor Terrlyn Foy said she was stunned to hear not only of Monroy’s death but also of who is alleged to have killed her.

Foy, who lives in a neighboring apartment building, said that in recent days she became attached to the children, even though they spoke almost exclusively Spanish. She said Monterroso had a warm personality but shared with her text messages that led her to believe the couple were having issues.

Still, she didn’t think he would harm anyone.

“That really, really shook me,” Foy said.

“He showed no evidence he was capable of doing something like that.”

Paul Ross, another neighbor, said he never witnessed any fighting between the couple.

Foy said Monroy seemed to be aloof when it came to her children.

She said she never saw Monroy hug them or hold them. Monterroso, meanwhile, seemed to have a better relationship with the children.

But ultimately it was the 12-year-old daughter, Jessica Nicolle, who appeared to be the main caretaker.

She would go to Foy’s apartment in recent days and use her stove to cook for her siblings and mother, communicating with Foy mostly through hand gestures.

“The 12-year-old basically was the mother. She watched over them (her siblings),” Foy said. “She (Monroy) basically was off to herself, always on the cellphone.”

Word of the arrest was welcome news to Foy but not nearly as much as the news that the children were unharmed.

“We’re so happy they were found safely,” she said. “I was praying for them.”

Follow Danny Monteverde on Twitter, @DCMonteverde.