The McHenry County Coroner's Office is waiting on additional tests to determine an official cause of death for a Marlowe Middle School student who died unexpectedly Monday. James "Jimmy" Kilanski was in the 7th grade, Marlowe Principal Tony Venetico said in a letter posted on the school's website. "We are all grieving this tragic loss and offer our deepest condolences to the Kilanski family, his many friends, his classmates, the teachers and staff members that learned alongside him, and to all who knew Jimmy," Venetico said.