Suburban Chicago U.S. Rep Sean Casten’s 17-year-old daughter, Gwen Casten, died Monday morning at the family’s Downers Grove home, the congressman’s office and Downers Grove police said. “This morning, congressman Casten’s beloved daughter, Gwen, passed away,” Casten’s office said in a statement Monday evening. “The Casten family requests privacy, and we will be issuing no further comment during this heartbreaking time.” Downers Grove police were called to a house in the block where Casten lives just before 7 a.m. Monday “for an unresponsive seventeen year old female,” according to a Police De…