The 911 caller was identified as the victim’s husband, 32-year-old Stephen Ray Lang, and he was later arrested for murder.
“As you fell, you tried to catch yourself and accidently discharged your firearm striking two of the juveniles,” Police Chief Jacquelyn Gwinn-Villaroel said in a memo to Kaiser on Jan. 25. “Your actions were unsafe.”
The shooting happened Thursday morning during a class on law enforcement scenarios.
The shooting was ruled accidental after an autopsy.
Police believe the child found a relative's gun and accidentally shot himself while playing with it.
The shooting happened July 31, on Spyglass Court in Okolona.
Police said the child is expected to survive.
The boy was taken to a hospital in critical condition, but police later said his condition improved to serious.
The case remains under investigation and no charges have been filed.
Police say it happened while the mother and toddler were "house-sitting" for relatives.