A message of support from the group Vets4Warriors will be visible during celebrations at the well-known site.
The event was one of several the Pentagon is holding to commemorate the 20th anniversary of the attacks.
Matthew Sullivan, 36, was sentenced in a San Diego courtroom for second-degree murder in the stabbing death of Elizabeth Sullivan.
Stafon Jamar Davis was sentenced in the July 2018 slaying of Abree Boykin.
