LITTLETON, Colo. — Sunday marked the 10th annual “Emily’s Parade,” the first held just 10 days after Emily Keyes was killed by the school gunman.

More than 4,000 motorcyclists started rode from Columbine High School to Platte Canyon High School in her honor and all of those lost to school violence.

Every year on the last Sunday of September, an event unites not just two Colorado high schools and communities but an entire nation with a shared history of school violence.

“Emily gave us a voice.  But she told us what to say.  I Love U Guys,” said John-Michael Keyes,, the father of the Platte Canyon High shooting victim.

The messages flowed, balloons flew and engines revved when the 45-mile journey began.

“A bunch of great people out here for a great cause,” biker Jason Rosales said.

Nine years ago to the day, Keyes lost her life to a school gunman who took six school girls hostage and sexually assaulted them before killing Keyes and himself as law enforcement stormed the classroom.

“Hearing the text that she sent, you know the last text was I love U Guys, it just shows us, you gotta let the people you love know that you love them because you never know what’s going to happen,” Columbine cheerleader Jays Show said.

Nine years ago, Flight for Life Colorado nurse Peter Werlin was there.

“We went up the stairs.  We ended up crawling through the hole in the wall and into the classroom and Emily and the shooter were both in the classroom. We just took over medical care of Emily right there,” he said.

Sunday, nine years later, he and thousands of others showed support for Emily, her family and the “I Love U Guys” Foundation.”

“It’s pretty special, Werlin said.

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The foundation, started for Emily, now encompasses so much more.

“It’s bigger than all of us.  It really is.  We have an absolutely fierceness of defending the symbols of this event and it is profound, it’s humbling,” said John-Michael Keyes, Emily’s father and executive director of the I Love U Guys Foundation.

Funded through Emily’s parade is the Standard Response Protocol, a program offered to all schools in the nation and Canada free of charge thanks to the money raised every year.

“One of the challenges that we saw as we looked at this is students, staff, first responders didn’t share a common language in any type of crisis.  And we found a common language that wasn’t based on codes or mystery words.  It’s just straight up.  Lockdown, lockout, evacuate and shelter,” John-Michael Keyes said.

Sunday is Emily’s Day.  In Colorado it is also First Responder’s Appreciation Day, thanks to Tim Gregg.

Gregg is the father of the other female hostage in the classroom when Keyes was shot. He’s working on getting the day named nationwide.