First responder, Angel Garza rushed to Robb Elementary School on Tuesday, May 24.
He was there to help the students and teachers injured in a Texas primary school mass shooting.
The medical aide arrived just as kids were being escorted from classrooms. He was drawn to one young girl who was covered in blood, from head to toe.
As he tended to her, he asked where she was injured.
"She said she was okay," Garza told CNN.
"She was hysterical, saying that they shot her best friend — that they killed her best friend, she was not breathing."
And then the young girl told him: Her best friend's name was Amerie.
Amerie Jo Garza. His daughter.
The young girl Garza was assisting was covered in his daughter's blood.
Amerie was just one of 21 devastating fatalities that occurred that day.
The Garza's story is particularly heartbreaking.
Watch Angel Garza speak to CNN about his late daughter, Amerie. Post continues below.
Amerie had turned 10 just two weeks before she was fatally shot at school on Tuesday.
To celebrate her birthday, her family gave Amerie her first cell phone, something she'd wanted dearly.
"She's been wanting a phone for so long and we finally got it for her," Garza explained.
"She was just trying to call authorities, and I guess he just shot her... I just want people to know she died trying to save her classmates. She just wanted to save everyone."
Garza recounted the story to a CNN journalist, Anderson Cooper between sobs.