Earlier on the day of the attack, Bryce’s mother had picked him up in Pleasant Prairie, Wis., where authorities said he was standing in a roadway, shirtless in a rainstorm. Laura Bryce drove her son home and was outside the house, talking on her phone to make treatment arrangements for her son, the attorneys said, when she heard a cry. When she came back inside, she saw Bryce attacking his father with the 10-inch-long garden shears, authorities said.