Joe Garcia, the husband of teacher Irma Garcia who was killed in the shooting, died of a heart attack on Thursday, according their nephew and a close family friend.

The two were set to celebrate their 25th anniversary this year. The couple had four children.

-ABC News' Alondra Valle

Evadulia Orta, the mother of 10-year-old Rojelio Torres, a fourth grader who died in the Tuesday shooting at Robb Elementary, told ABC News that she is trying to stay strong for the rest of her children, but "I lost a piece of my heart," she said.

The mother of four told ABC News she went to pick up two of her children at the school, but only came home with one.

This has not only devastated her entire family, but the community, she said, speaking with her twin sister.

"We are praying for everyone, all the children and all the families," she said.

-ABC News' Maria Elena Salinas

Bob Estrada, who lives across the street from Robb Elementary School, recounted to ABC News the moments he went out on his porch after hearing gunshots, saying he witnessed the police response to the shooting unfold.

Estrada, whose grandson is a second grader at the school who survived the shooting, said he saw "quite a few" officers outside the school immediately, and then police cars started driving up -- but "some of them just stood there."

"Why aren't they going in?" Estrada told ABC News he wondered at the time.

Estrada said it was not long before parents began to arrive. "They were hysterical," he said.

"There were parents out there, and they were kinda motioning like they wanted to come in," Estrada said. "They were motioning like, 'What are you doing? Go in!'"

Estrada said he did see some officers go in immediately.

Asked if he saw reinforcements heading into the school, Estrada said no. But, he did not know what sort of presence may have already been inside.

-ABC News' Matt Gutman, Olivia Rubin, Jeffrey Cook and Laura Romero

The young girl who allegedly received messages from the Texas gunman moments before his rampage told ABC News she has been asking herself "what if I could change the outcome" since seeing the news that her friend killed 19 students and two teachers on Tuesday.

"Ever since May 24th I have been guilt tripping myself, what if I could change the outcome, what if I could change his mind to not do this. I was too dumb to realize why he bought two Rifles on his birthday May 16th and ordered a package full with ammunitions not knowing what he was going to do with it," the 15-year-old girl, who asked to be referred to as "Cece," told ABC News.

The messages are part of an ongoing investigation into the shooter, law enforcement sources told ABC News.

Cece, who lives in Germany, said she met the accused gunman on the social media app Yubo where they would "join each others live" streams. The pair met on the app on May 9 before exchanging cellphone numbers, Cece said.

The messages reviewed by ABC News and other outlets appear to show that Cece did not respond to the gunman's threats until after news of the shooting broke and nearly all the texts are solely from the suspect. It is unclear if the messages were at all edited.

-ABC News' Will Steakin

A fourth-grade teacher and a 10-year-old boy were among those killed, ABC News has learned.

The teacher, Eva Mireles, had worked in the school district for approximately 17 years, her aunt, Lydia Martinez Delgado, confirmed to ABC News.

Fourth-grader Xavier Lopez was among the 19 children killed.

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