the mother drove to the cellphone repair store at 1:50 p.m. and left the children in the minivan. The 6-year-old later told investigators the baby started fussing, and he wanted to calm her down. He lifted the infant from the car seat and tried to mimic how his mother would calm her. Instead the boy actually ended up repeatedly slamming the baby’s head into the minivan’s ceiling and dropping her to the floor, flipping the baby over and over and pummeling her, said deputies. When Steele returned to the car the 6-year-old boy tried to tell her there was something...