In Dallas, Texas a five-year old boy was shot and killed by an eight-year old who found a loaded gun.  Authorities announced that they are investigating how the 8-year old got access to the gun.  No other details have been released.

Source:

Jozelyn Escobedo, “5-year-old Boy Dies After Being Shot by Another Child in Dallas Apartment, Police Say,” wfaa.com (June 5, 2021).