Shortly after the Sept. 11, 2001, terrorist attacks on the World Trade Center, someone constructed a wooden plaque in Fieldston’s Endor Garden honoring five local first responders who died that day. But someone stole the display in 2017, leaving it empty ever since. Laura Spalter and others are set to change that Saturday with the unveiling of a new plaque in time for the 20th anniversary of 9/11.