Willie Keil’s grave sits on a hilltop in the Willapa Valley. The marker is a bit hard to read — the weathered stone shows a date of death as May 19, 1855. What’s unusual about Willie’s case isn’t when he died, but where: Willie succumbed to disease in Bethel, Missouri, 2,000 miles away, days before his family hit the road west, along the Oregon Trail. So how did this 19-year-old wind up buried not in Missouri, but in Southwestern Washington? “The story goes that Willie …. was extremely excited