Slash the chocolate Lab jumped into Kate Rondelli's bed in the middle of the night Tuesday, licking her face to wake her up. There was trouble. The dog led her to her son's room, where Rondelli tested her 4-year-old's blood sugar levels: Over 400 milligrams per deciliter, more than twice the maximum range desirable for the little boy with Type 1 . Rondelli quickly gave her son, Mylon, insulin to stabilize his levels, averting a possible medical emergency. "His nose is always working," Rondelli said. Slash is a diabetes detection dog, trained to alert Rondelli when her son's blood sugar falls or spikes to potentially dangerous levels. The dog and his new family visited the Bunker Hill Fire Station in Prince George's County, Maryland on Wednesday to get acquainted with first responders as part of Slash's training. Service dogs can be protective of their owners, so Rondelli and Slash's trainers wanted to make sure that if firefighters have to be called to the house for a medical emergency, Slash would be familiar with people in uniform and stand down to let medics treat Mylon. The dog visited the firehouse in Brentwood twice so that "when we show up for a call, not only Mylon but Slash is familiar with us being there and us being in close contact with Mylon," said James Key, acting battalion chief for the Prince George's County Fire Department. "The first time Slash will meet us is not when we come with lights and sirens." Erin Gray, with the organization that trained Slash, said diabetes dogs, like bomb-sniffing or drug-sniffing dogs, are trained to detect smells as a way to alert people to trouble. In Slash's case, he was taught to detect acetone scents coming from Mylon's body as a signal of low blood sugar and sweet, syrupy smells as an indication of high blood sugar. "He gets rewarded when Mylon is out of range," said Gray, a trainer with Service Dogs by Warren Retrievers based in Virginia. Dogs like Slash go through an extensive training and obedience program for nine to 18 months before they are delivered to families, Gray said. After that, each dog is customized to the needs of the person they serve. Mylon was diagnosed with Type I diabetes two years ago,