14-year-old Jaime Guttenberg was killed alongside 13 of her classmates and three school staff members on February 14, 2018.
"Exactly one year ago, to the minute at around 7am, I sent two kids to school," Fred Guttenberg tweeted Thursday morning.
"Only my son Jesse came home. Jaime was murdered in school. I am forever haunted by my memory of that morning, rushing my kids out the door rather than getting one last minute. Did I say I love you?"
Jaime Guttenberg was a straight-A student, a talented dancer, and an aspiring pediatric physical therapist.
"It was not supposed to be the the last time I would see Jaime," Fred Guttenberg said in another tweet. "For those who still want to deny the reality of gun violence, my daughter IS Jaime Guttenberg."
"I will be visiting her today at the cemetery. Jaime, I love you forever and miss you every second of every day."
In the year since the shooting, the deadliest high school shooting in US history, Guttenberg has become a staunch advocate for gun control, launching a national anti-gun-violence movement.
Guttenberg attended the 2018 State of the Union address as the guest of Nancy Pelosi, now the Speaker of the House, and has confronted Republican lawmakers over gun control legislation.
In February 2018, he criticized a listening session President Donald Trump held with survivors and family members of victims of school shootings.
"I want them to look me in the eye and acknowledge the role that guns play in the hunting of my daughter," he said at the time.
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