According to reports, McKayla Dyer was playing outside in the garden before the shooting happened.
Her mother, Latasha, told WATE News that McKayla was approached by the 11-year-old boy, who is a neighbour.
According to reports he asked if he could see her puppy.
When she told him no, Dyer said the boy went back to his Tennessee home, retrieved his father’s 12-gauge gun and shot her in the chest.
McKayla was rushed to a local hospital, but tragically died of her wounds.
Her mother emotionally told WATE: "She was a precious little girl, she was a mommy's girl, no matter how bad of a mood you were in she could always make you smile.”
The shooting wasn’t the first time their family had problems with the boy, devastated Latasha added.
“When we first moved to White Pine, the little boy was bullying McKayla.
“He was making fun of her, calling her names just being mean to her, I had to go the principal about him and he quit for a while and then all of a sudden yesterday he shot her.”
The boy, who has not been named publicly, has been arrested and charged with first-degree murder.
He is currently being held in a juvenile facility.
Latasha Dyer said: “I want her back in my arms, this is not fair, hold and kiss you’re babies every night because you’re never promised the next day with them.
“I hope the little boy learned his lesson because he took my baby’s life and I can’t get her back.”
The boy’s next court date is 28th October, when his case could potentially be moved to adult court.