The incident occurred just before 2:00 p.m. Tuesday in the 200 block of East Hazeldell Avenue in Minquadale.
The Minquadale Fire Company responded to the report of a grass fire.
State fire investigators were called to the scene when it was learned that a young boy had been burned at the same location and taken to the Wilmington Hospital by a member of his family.
The victim has been transferred to the Crozer Burn Center in Upland, Pennsylvania with 2nd and 3rd degree burns to his face and chest.
He is listed in critical condition.
Officials say the fire began when a person used gasoline to start a barbecue grill.
The gasoline vapors erupted into flames causing the burns to the child who was nearby when the grill was ignited.
Fire officials say gasoline is an extremely flammable liquid and should never be used as an accelerant for any method of cooking.
The house is about a half-a-block from Minquadale Fire Company.