Woman who lost 2 grandchildren in Oklahoma City bombing on why she’s forgiven Timothy McVeigh

A woman who lost two grandsons in the 1995 Oklahoma City bombing spoke out on why she's forgiven convicted bomber Timothy McVeigh.

McVeigh detonated a truck bomb outside of the Alfred P. Murrah Federal Building on April 19, 1995. A total of 168 people died, including 19 children, in what remains the deadliest act of domestic terrorism in American history.

McVeigh received the death penalty and was executed in 2001, while co-conspirator Terry Nichols was sentenced to life in prison.

Kathy Sanders appeared on TODAY on April 12, along with Katie Couric, to talk about a new documentary about the bombing.

Sanders says she has managed to forgive McVeigh for the deaths of her two young grandsons, Colton and Chase Smith, who were killed in the blast.

“Forgiveness is a process," she told Savannah Guthrie. "It’s not an event (that) just happened overnight. It’s the biggest gift you can give yourself.

“To harbor bitterness and hatred and anger in your heart is like drinking poison and expecting the enemy to die. It does you no good.”

The tragedy is the subject of a new HBO documentary, “An American Bombing: The Road to April 19th,” which dives into what led to it and the continued fight against domestic terrorism. Couric is the film's executive producer.

Couric has interviewed Sanders multiple times over the years and was the first person to speak with her and her daughter after the bombing.

“Obviously, I was so drawn to them and to the story,” she said.

“We cover so many stories, so many tragedies, but to be able to follow something and to follow Kathy and the amazing things she’s done and the way she has healed through he compassion and humanity and grace — other family members, as well — it’s been really life-affirming for me to cover this story, even though it was such a tragedy."

“An American Bombing” shines a light on the families affected by the bombing, but also peels back the curtain on how the event served as an origin point for what's become a widespread problem in the country.

“I think it really focuses, obviously, on families and their stories, but it’s juxtaposed against a whole series of events that led up to April 19, 1995, in Oklahoma City,” Couric said. “It really weaves together these white power groups and right-wing extremism and how it grew and festered and metastasized, really, like a cancer.”

“An American Bombing: The Road to April 19th,” premieres April 16 at 9 p.m. ET on HBO. It will also be available to stream on Max.

This article was originally published on TODAY.com