The family of 13-year-old Isaih Cantu has been left torn by his shooting death last Friday.
Erica Cantu said she rejects claims by Jesus Trevino, her nephew, and his mother, her sister, that Trevino accidentally shot her son in the head.
Cantu said, "If it was an accident, why did he cock the gun before he put it to his head?"
She also said, "It was his gun. How did he not know it was loaded?"
San Antonio police charged Trevino with murder following the shooting Friday at an apartment complex in the 500 block of Everest.
Trevino, who was already on probation, remains under a $100,000 in the Bexar County Jail.
Cantu said due to personal problems and being homeless for a time, her sister had been Isaih's guardian for the past year.
"I need her to know I am not blaming her for what happened," Cantu said.
But as for Cantu's nephew, she said, "You deserve to be in prison for the rest of your life. I will never forgive you for what you did to my son."