A 16-year-old boy got into an argument with his family when he didn't want to get out of bed and go to school and he shot his grandmother, a younger sister and a 6-year-old nephew, authorities said.Police said in a statement that the boy's mother and grandmother told investigators that he got angry Tuesday when they told to him to get up. He made threats and went to a closet, got a handgun that nobody in the household knew he had and started firing inside the family's apartment, police said.His 67-year-old grandmother was struck by bullets at least twice and the nephew and 12-year-old sister suffered graze wounds. The boy's 2-year-old sister and mother were in the apartment, but neither was injured by the gunfire.The boy fled on foot and dropped off the gun at a nearby apartment, police said. The teen was captured a short time later near railroad tracks.The family members are expected to survive. The teen has been charged with four counts of attempted homicide and one count of reckless endangerment.