KATHERINE A. ROELTGEN, a nurse, died Mar. 6, 2017, at age 36. She received a master’s degree in nursing from Yale University in 2008. A volunteer with Doctors Without Borders, most recently in the South Sudan, she also worked at New York Presbyterian Hospital and at Brooklyn Methodist Hospital. Her parents, David and Margaret Roeltgen, survive, as do two brothers, two aunts, three nieces and nephews, and many cousins.