Good things come in small packages – like 3-year-old Cohen Chastain, who stood at attention for more than two hours at a funeral procession for fallen Polk County Detective Kristen Hearne. Cohen, a preschooler from Rockmart, Ga., decided to show his support all on his own. “It was all his idea,” Cohen’s mother, Mandy Chasten, told TODAY. “He had a lot of questions with all the police officers at church that day and I decided I should just tell him the truth. He was really heartbroken when I explained what had happened and he wanted to wear a police uniform and stand…