Family members said the shooting, which happened shortly before 11 a.m. Saturday at 829 S. Tillery St., was a terrible, heartbreaking accident.
The older sister, whose age police did not disclose, got hold of what she thought was a water gun and shot the toddler once in the head, relatives said
The 2-year-old was taken to Nash General Hospital and then airlifted to Pitt Memorial Hospital in Greenville. She remained in critical condition Monday.
"She's a sweet little girl," her aunt Evelyn Davis said. "I can't hardly say much right now, because I'm hurting very bad."
Investigators did not say who owns the gun or how the older girl obtained it. Officers emphasized that the shooting was accidental.
Police questioned the girls' mother and her boyfriend and have talked to the local district attorney's office about any associated charges. No decision on whether the adults might be charged has been made.
Officers said they would withhold the identity of the victim unless the family chose to release that information.