CHICAGO (STMW) — An 18-year-old man was sentenced to 30 months in prison today for bringing home a gun that was later found by a young nephew who accidentally used it to fatally shoot his twin brother.

Antoine Heard pleaded guilty to endangering the life of a child, causing death, said Tandra Simonton, a spokeswoman for the Cook County state’s attorney’s office.

Heard has been at the Cook County Jail since being charged for the Aug. 9 shooting that killed Jonathan Jackson, 5, at the boy’s home on the 700 block of South California Avenue.

The boy’s twin brother accidentally shot Jonathan as they played with the gun — a Hi-Point .380 with four live rounds — that Heard hid in an older sister’s room.

He said he found the gun weeks earlier and hid it in the room, knowing that the twin brothers slept and played in the room. He hid the gun behind a television and under the boys’ clothing and toys, said Simonton.

Heard was found delinquent three times as a juvenile for drug offenses and violated probation in 2009. He will be credited for serving 295 days at the Cook County Jail.

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