By Rich McKay (Reuters) – A carbon monoxide leak sent dozens of children and staffers at a Pennsylvania daycare center to local hospitals on Tuesday in an evacuation that drew every ambulance in the city of Allentown to the scene, authorities said on Tuesday. At least 28 children and seven adults were involved in the incident, which began with a report of an unconscious child at the Happy Smiles Learning Center shortly before 7 a.m., said Allentown Fire Chief Efrain Agosto. “I’m told all are stable and thank God, everyone is going to be fine,” Agosto said. “This could have turned out really ba…