(CBS News) - Ava Olsen always carries Mikey, the Ninja Turtle that belonged to her friend Jacob. When she looks at Mikey, she thinks that "Jacob's with me."
Jacob Hall, the boy Ava imagined marrying, was six. In September of 2016, he was shot and killed on the school playground in Townville, South Carolina.
The shooter was fourteen. Ava watched it happen.
"I always try to forget it, but it doesn't work," she said.
Mary and David Olsen, Ava's parents, now homeschool her. The eight year-old has been diagnosed with severe PTSD.
"The rage," Mary said. "Yelling."
"You can tell because her pupils get dilated and she just doesn't remember anything until it's all over with," David said.
Ava decided to do something about it.
"I wrote the president a letter," she said. "Because presidents are a pretty big deal."
She used her best handwriting. "Dear Mr. President, I heard and saw it all happen. And I was very scared. I don't want that ever to happen again. Are you going to keep kids safe?" she wrote.
Two months later, the president wrote her back.
"Dear Ava," the president's letter said. "Thank you for your letter. It was very brave of you to share your story with me. Schools are places where children learn and grow with their friends. Their halls should be free of fear."
"It was nice to hear he prayed for me," Ava said.
Did it say help?
"I wanted him to say how," Ava said. "That's why I wrote the second letter. You know, adults sometimes don't like to ask for help."
She said she thought she would give him the help. In her second letter to the president, Ava suggested ways to keep kids safe.
She has yet to hear back a second time. She says she is feeling "sad, mad, scared" these days.
Ava Olsen has no physical scars, but she was wounded in a schoolyard shooting.