Thadd McNamara was at the helm of his motor home on a cross-country trip in 2005 when his cellphone rang and a neighbor gave him the news: His grown son, Sean, was in trouble with law -- again. ... It turned out Sean McNamara was accused of burglarizing his father's home and attempting to make off with a baseball cap bearing the logo "Snap-On Tools." It was classic Sean, his father would later say. Nothing serious. Just another knuckle-head move from an overgrown kid who drank too much beer, didn't pay his bills and, essentially, refused to grow up. Thadd...