A 4-year-old boy drowned in a pool in North Brunswick on Saturday night, authorities said. Police got a 911 call at 7:46 p.m., on Saturday, reporting that the boy had been found in “a residential pool” and wasn’t breathing, Middlesex County Prosecutor Yolanda Ciccone and North Brunswick Police Chief Joseph Battaglia announced Sunday. CPR was performed on the boy, who was taken to Robert Wood Johnson University Hospital in neighboring New Brunswick, where he was pronounced dead. “Our hearts are heavy with this tragic loss,” Ciccone and Battaglia said in a joint statement. “We extend our deepest…