Hashtag 'EmptySeat' Commemorates Gun Violence Victims at SOTU

— -- One of the most talked-about guests at tonight's State of the Union won't be there.

President Obama's team announced that among the honored guests seated alongside the First Lady will be a chair left purposefully empty to remember victims of gun violence.

In the lead up to the President's speech, Twitter users created a hashtag -- #emptyseat -- for their own remembrances.

Over the past few days, the hashtag has been used almost 16,000 times, including many from shootings that did not gain national attention. Some, however, featured victims from the movie theater shooting in Aurora, Colo. in July 2012 like Alex Sullivan.

Others featured the children and staff members killed at Sandy Hook Elementary School in Newtown, Conn. in Dec. 2012.

And another included a picture of Alison Parker, a reporter who was shot alongside a colleague during a live news broadcast in Roanoke, Virginia in August 2015.