"She had so much to offer the world and had so much ahead of her", he said.
The federal government's failure to pass any meaningful gun laws, despite support from the President for ideas such as raising the minimum age to buy an assault rifle to 21, has also focused attention on the National Rifle Association's donations to lawmakers.
Emma, 18, is a student at Marjory Stoneman Douglas high School in Parkland, Florida.
"We, the youth of the United States, have built a new movement to denounce gun violence and call for safety in all of our communities".
The main talking point however was the speeches, with a host of inspiration figures taking to the stage, from Yolanda Renee King, Martin Luther King Jr.'s nine-year-old granddaughter to 11-year-old Naomi Waddler who led a walkout at her primary school to bring attention to gun violence.
Joan Howard, whose son Kempton was shot to death in 2003, said that while Canada doesn't experience mass shootings on the same scale as the US, it's hardly immune.
Gonzalez's pause represented the time it took the alleged shooter, Nikolas Cruz, to carry out the shooting. "My colleagues are innocent, my son, all these kids are innocent".
"I feel we're all part of a family here", said Tanner Bailey, of Wisconsin.
Gun control supporters expressed outrage when the image was shown to be fake. She stopped talking and the crowd didn't know what to do.
In addition to the main event, hundreds of other solidarity protests took place around the globe - and on every continent except Antarctica - as demonstrators called for common-sense gun reform.
Rallies were also planned in most major Canadian cities, including St. John's, Ottawa and Calgary. People continued to pour into the park throughout the rally. "For those who still can't comprehend because they refuse to, I'll tell you where it went: right into the ground, six feet deep". She said it's hard to talk about the "terror, confusion and panic". Throughout his impassioned speech, Cameron added he felt hopeful: "For the first time in a long while, I look forward 10 years and I see hope; I see light; I see a system I'll be proud of, but it all starts with you".