'She Was Trying to Call 911 and He Shot Her': Texas Shooting Victim Amerie Jo Garza, 10, Remembered As 'Hero'

Amerie Jo Garza received an Honor Roll certificate minutes before the shooter opened fire in her classroom

Angel Garza, Amerie Jo Garza. Photo: GoFundMe

A 4th grade student has been identified as one of the victims in the Robb Elementary School mass shooting in Uvalde, Texas, on Tuesday.

Amerie Jo Garza — a doting sister who family members are remembering as a hero — celebrated her 10th birthday just two weeks before she was fatally shot, her grandmother confirms to PEOPLE.

According to Berlinda Arreola, 49, Amerie was one of the first children shot to death by 18-year-old gunman Salvador Ramos, as she tried to dial 911 on her cell phone.

"He could have just taken her phone away," Arreola says. "He could have just broke it, done something. And he just shot her."

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"She was a hero trying to call 911, to save her and her friends," says the grieving grandmother.

At just 10 years old, Arreola says Amerie was instinctively helpful and protective, especially when it came to her little brother, 3-year-old Zayne, whom Amerie remembered to kiss every morning before she went to school, where she also excelled as a student and won the school's "Heart of Gold" award last year.

In fact, Amerie's scholastic achievements were recognized when she received an Honor Roll certificate minutes before the shooter stormed her classroom and killed her and her classmates, Arreola says.

Now, the family of the little girl who loved her baby brother and enjoyed drawing and swimming in her spare time is preparing to bury her.

"My little love is now flying high with the angels above," Amerie's dad Angel Garza wrote on Facebook. "Please don't take a second for granted. Hug your family. Tell them you love them. I love you Amerie jo. Watch over your baby brother for me."

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Investigators have not discussed a motive for the mass shooting about 85 miles outside of San Antonio that left 21 people dead, including 19 students.

Authorities have said that, prior to traveling to the school, the shooter shot his grandmother, who has so far survived her injuries.

Hours after the massacre, President Joe Biden addressed the nation in a nearly eight-minute speech, saying in part, "I had hoped when I became president I would not have to do this again, another massacre in Uvalde, Texas. An elementary school. Beautiful, innocent second, third, and fourth graders. How many scores of little children who witnessed what happened, see their friends die, as if they're in a battlefield for God's sake."

Continued Biden: "Parents who will never see their child again. Never have them jump in bed and cuddle with them. Parents who will never be the same. To lose a child is like having a piece of your soul ripped away. There's a hollowness in your chest; you feel like you're being sucked into it and never going to be able to get out, suffocating. It is never quite the same. It's a feeling shared by the siblings, the grandparents, the family members, the community that's left behind."

The school district in Uvalde has opened an official account with First State Bank of Uvalde to support Robb Elementary families affected by the tragedy. People can send checks through the mail (payable to the "Robb School Memorial Fund") or donate money through Zelle to [e-mail]. People can also donate by calling 830-356-2273.

Updated by Wendy Grossman Kantor