Illinois Rep. Sean Casten, a Democrat, announced Friday that his daughter's death in June was from a cardiac arrhythmia. "This past June, our daughter, Gwen Casten, died of a sudden cardiac arrythmia. In layman’s terms, she was fine, and then her heart stopped," the Casten family wrote in a statement. Gwen Casten, 17, died peacefully in her sleep in June after eating dinner with her parents and then going out with friends for a few hours. -snip- The family said Gwen was a healthy teenager who ate well, exercised, received regular medical check-ups, did not suffer from any behavioral issues...