"It's done nothing in the last six years but bring horror," one mom said.

This week, demolition will begin on the 1200 building at Marjory Stoneman Douglas High School in Parkland, Florida.

Fred Guttenberg, who lost his daughter Jamie in the 2018 school mass shooting, speaks with ABC News' Rachel Scott about his push for more gun control.

Seventeen students and staff were killed in the February 2018 Stoneman Douglas massacre.

Six Members of Congress visited Parkland, Florida, on Monday to tour the site of the Marjory Stoneman Douglas High School mass shooting.

Manny Oliver, who lost his son Joaquin to the 2018 mass shooting, spoke with ABC News Live.

ABC News’ Phil Lipof spoke with Manuel Oliver, the father of Joaquin Oliver, on what would have been his 23rd birthday, and how he hopes to prevent families from experiencing similar tragedies.

The Parkland, Florida, high school massacre will be reenacted in the same building on Friday as a part of a lawsuit.

The reenactment is part of a civil lawsuit against former officer Scot Peterson to prove he heard the gunshots.

Families of the Parkland victims are now allowed to visit the 1200 building where students and staff were killed at Marjory Stoneman Douglas High School.

The former Parkland Florida school security officer was accused of failing to confront the gunman who murdered 17 people in 2018.

Scot Peterson, the ex-Parkland resource officer accused of allegedly failing to confront the school shooter, has been found not guilty.

Scot Peterson, the former resource officer accused of failing to confront the Marjory Stoneman Douglas High School shooter, was found not guilty on all counts.

Scot Peterson, the former Parkland, Florida, school resource officer who didn't confront the gunman, has been found not guilty on all counts of felony child neglect.

The former sheriff’s deputy is accused of standing by during the 2018 massacre at Marjory Stoneman Douglas High School. ABC News' Derricke Dennis has the opening statements from court.

Jury selection is set to begin Wednesday in the trial of Scot Peterson, a former school resource officer charged in connection with the Parkland school shooting.

The parents of Parkland victim Joaquin Oliver are bringing their new "children's book" to Washington, D.C., lawmakers in an effort to shine a light on gun control.

ABC News' Phil Lipof spoke with 2018 Parkland shooting survivor Samantha Fuentes following the latest mass shooting at a Denver high school, and five years after the “March For Our Lives” rally.

Manuel Oliver and his wife, Patricia Oliver, were removed from a House subcommittee hearing by Capitol Police officers at the direction of Chairman Pat Fallon

The mother of one of the teachers killed in the massacre at Marjory Stoneman Douglas High School talks about the fight to stop mass shootings on the five-year anniversary.

Five years after the mass shooting at Marjory Stoneman Douglas High School, Florida Reps. Jared Moskowitz and Maxwell Frost reflect on where the country is now.

With the threat of gun violence on their minds, teachers are struggling with how to protect their students while worrying about their own safety.

The Parkland School shooter, who killed 17 people at Marjory Stoneman Douglas High School in 2018, has been sentenced to life in prison without parole on 34 counts of indictment.

Nikolas Cruz, who shot 17 students and staff members in Parkland, Florida, in 2018, has been sentenced to life in prison by a judge.

Lori Alhadeff, whose daughter died in the mass shooting at Marjory Stoneman Douglas High School, gave her victim impact statement in front of convicted killer Nikolas Cruz.

Families of Parkland high school massacre victims confront shooter as he is officially sentenced to life in prison.

Survivors and family members of the 2018 shooting in Parkland, Florida address gunman Nikolas Cruz in court sharing victim impact statements.

Bree and Eric Wikander spoke on behalf of their son, who was shot in the back.

Anthony Montalto criticized the jury for deciding against sentencing gunman Nikolas Cruz to death for murdering 17 people on February 14, 2018.

Ines Hixon was the daughter-in-law of Chris Hixon, the athletic director and wrestling coach at Marjory Stoneman Douglas High School, who was killed in the attack.

The teen gunman pleaded guilty to killing 17 people at Marjory Stoneman Douglas High School in 2018 and is expected to be sentenced to life in prison.

The families of the victims of the massacre at Marjory Stoneman Douglas High School will give impact statements ahead of the sentencing.

Anne Ramsay’s 17-year-old daughter Helena died in the mass shooting at South Florida's Marjory Stoneman Douglas High School.

Terri Rabinovitz, the grandmother of 14-year-old victim Alyssa Alhadeff, addressed gunman Nikolas Cruz in court during the victim impact statements.

The jury recommended life in prison for Nikolas Cruz, who killed 17 students at Marjory Stoneman Douglas High School. The verdict frustrated Florida’s governor and the community.

Linda Beigel Schulman – the mother of Scott Beigel, a teacher killed in the 2018 Parkland, Florida, school shooting -- speaks out after a jury ruled the gunman should not face the death penalty.

Fred Guttenberg, the father of Parkland victim Jaime Guttenberg, discusses the jury’s recommended sentence of life without parole for the school shooter.

Nikolas Cruz was spared the death penalty and sentenced to life in prison by a Florida jury for carrying out the massacre at Marjory Stoneman Douglas High School in 2018.

ABC News' Linsey Davis spoke with Manuel Oliver, the father of Joaquin Oliver, about a jury's decision giving a life sentence to the Parkland shooter.

The Parkland school gunman Nicholas Cruz has been sentenced to life in prison by a Florida jury. He was spared the death penalty.

The judge set a sentencing date for Nov. 1 for the gunman who pleaded guilty to killing 17 people in a shooting at Marjory Stoneman Douglas High School in February 2018.

Parents of Parkland shooting victims react after the jury recommends the shooter be sentenced to life in prison.

Nikolas Cruz pleaded guilty last year to 17 counts of first-degree murder and 17 counts of attempted first-degree murder.

A jury in Florida is set to deliberate the sentence for Nikolas Cruz, the shooter who confessed to killing 17 people at Marjory Stoneman Douglas High School.

Prosecutors are asking jurors to sentence the man responsible for the Parkland, Florida, school shooting to death. ABC's Andrea Fujii has closing arguments from both sides.

The fate of confessed Parkland shooter Nikolas Cruz will soon be in the hands of the jurors.

Confessed Parkland school shooter Nikolas Cruz's attorney gave her opening statement to the jury on Monday.

The jury will determine if Nikolas Cruz will be sentenced to death for killing 17 people.

Families of Parkland victims are addressing the court Monday during the penalty phase of the confessed shooter's trial.

Families of those killed during the 2018 Parkland school shooting gave victim impact statements during the penalty phase of the gunman's trial.