An advocacy group, Avaaz, placed 7,000 pairs of children's shoes on the lawn - each pair representing the life of a child killed by gun violence since the horrifying Sandy Hook Elementary School shooting in 2012 in CT. Shortly after the Parkland shooting, the group set up a trio of billboards, near Marco Rubio's Florida headquarters.
According to a press release issued in advance of the event, the figure of 7,000 came in part from an American Academy of Pediatrics study.
About 1,300 people below the age of 18 are killed by gunfire in the United States every year, according to the U.S. Centers for Disease Control and Prevention. That breaks down to 3.5 killings each and every day.
One of the parents who attended the protest on Tuesday was Tom Mauser, whose 15-year-old son Daniel was killed in the 1999 Columbine shooting.
"You can just remember her smile", her mother Barbara said.
The Parkers were among the dozens of volunteers at the Capitol calling on Congress to take action. It's a visual protest, no posters necessary, with a clear message: #NotOneMore.
Lori Haas was also there, speaking with WUSA9 about her painful memories. Organizer Emma Ruby-Sachs said she thinks it's a pivotal moment for the movement to end gun violence.
Gun control advocates and students seized on the most recent school shooting to call on Congress to take up legislation to tighten background checks and restrict access to certain weapons.
Fortunately that phone call would not be their last.
"The numbers are so gross in this country", she told WUSA.