MADISON - A Brooklyn man who stole his mother's handgun and ammunition and traded them for heroin was sentenced Tuesday in federal court to three years in prison for being a felon in possession of a firearm. Jason I. Kestler, 36, was brought up in a financially stable family and developed a good work history and marketable skills, but by 21 years of age he was abusing drugs and alcohol which lead to his problems with the law, his attorney Joseph Bugni said. Kestler had five Operating While Intoxicated convictions and was on probation in Sauk and Columbia counties for possessing narcotics and false imprisonment last December when the drug dealer he traded the handgun to turned him in, said Assistant U.S. Attorney Peter Jarosz.