The teen was a student at Marjory Stoneman Douglas High School in Parkland, Florida, and one of 17 people killed in the Valentine's Day shooting in 2018.
A grieving father was arrested while sending a message to the president on the fourth anniversary of his son's death.
Manuel Oliver climbed a 150-foot crane at a construction site near the White House to fly a banner with the image of his son, Joaquin.
"Four years later feels like it's like this morning," Patricia Oliver, Joaquin's mom, said.
"So this is a day. This is a day that remarks the day that we lost Joaquin, but really, every day reminds us the pain. And that's why we decided to be where we are today, fighting hard."
The Olivers are now dedicating their lives to seeing changes to the country's gun laws in hopes of preventing future deaths.
Their newest project is the website Shockmarket.org, which will track deaths and injuries caused by gun violence.
"The way they care about how the stock market works, they have to care how many people is losing by gun violence every single second of the day," the mother added.
Oliver and two other people were charged with unlawful entry and destruction of property.
The White House issued a statement about the fourth anniversary of Parkland, saying it stands with those working to end the epidemic of gun violence.