A 4-year-old boy found an unsecured gun in a car and fatally shot his 2-year-old relative in Kissimmee, Florida.

A 4-year-old boy shot and killed a 2-year-old boy with a gun that was left unsecured in a car, according to authorities in Florida.

A 4-year-old boy found an unsecured gun in a car and fatally shot his 2-year-old relative in Kissimmee, Florida.

The 2-year-old's mother and her boyfriend were home at the time of the shooting, and both were arrested, authorities said.