An investigation into the Mother's Day 2009 murder of Stacey Burns of Wolfeboro, N.H., a school nurse and a divorced mother of five. Also: a report on vervet monkeys on the Caribbean island of St. Kitts stealing alcohol from outdoor bars and drinking it. The report also focuses on what scientific studies of inebriated monkeys reveal about human drinking patterns. Correspondents: John Quinones and John Berman