When DeMarcus Cousins was growing up in Mobile, he experienced a natural disaster. “A tree fell on our house during a hurricane,” he said. He remembers neither the year, the name of the severe storm nor the extent of the damage. “I was young,” he said. He’s 20 years old now and just finished his rookie year in the NBA as a center with the Sacramento Kings, and on Friday, the former standout from Erwin and LeFlore high schools and two other pro basketball players from Alabama toured neighborhoods hit hard by a deadly April 27 tornado.