18-year old Fernando Akins of Nashville, Tennessee mishandled a gun in his home and accidentally shot and killed his 17-year old half-brother, Elton Maupins.  After the accident, Akins went to get his grandmother and the two of them rendered aid, but Maupins later died at the hospital.  The gun used in the incident has not been recovered.

Sources:

Ethan Illers, “Teen in Custody for Deadly Shooting of Half-brother,” wkrn.com (January 21, 2022).