“To the parents and families of those affected by the tragic events at Apalachee High School, I want to say that I am so sorry from the bottom of my heart,” Marcee Gray, the mother of Colt Gray, wrote in the letter which she provided to CNN.

“If I could take the place of Mason and Christian, I would without a second thought,” she said, referring to the two 14-year-olds killed in the mass shooting. She later added that her “heart breaks for the 2 teachers who gave their lives while in the service of teaching and protecting our children.”

The mother continued: “We are all in a living nightmare right now, and I will personally never forgive myself for what has happened.”

“My son Colt is not a monster. He is my oldest baby. He is quiet, thoughtful, caring, funny, and extremely intelligent. Please pray for him and the rest of our family, as I am praying for all of you every moment of every day,” she wrote.

Her letter comes one week after the teen allegedly carried out the shooting that left two teachers and two students at Apalachee High School dead.

Seven others at the Winder, Georgia school were wounded by gunshots and two others suffered other injuries in the attack, officials said.

In the days since the shooting, it has been revealed that the boy’s mother allegedly warned school officials 30 minutes before the attack.

Marcee Gray made a frantic call to the school counselor just before 10 a.m. the morning of the shooting after her son texted her “I’m sorry.”

“The counselor said, ‘I wanted to let you know that earlier this morning, one of Colt’s teachers had sent me an email saying Colt had been making references to school shootings,’” Marcee Gray told ABC News.

“Between my gut feelings, the text messages, and now this email, you need to, like, run to the classroom,” she said.

Gray later texted her sister, Annie Brown, that she alerted the counselor that it was an “extreme emergency” and that the school should “immediately” take steps to find the boy.

Authorities said Colt opened fire about 30 minutes after his mother’s warnings. They said school resource officers tried to track down Colt in his classroom, but stopped a different student with a similar name instead.

Minutes later, Colt allegedly opened fire in the halls of the school, killing two students, two teachers and injuring nine others.

Authorities said Colt opened fire about 30 minutes after his mother’s warnings. They said school resource officers tried to track down Colt in his classroom, but stopped a different student with a similar name instead.

Colt surrendered after being confronted by a school security officer and was quickly taken into custody. He has been charged with four counts of felony murder.

His father Colin — who allegedly bought his troubled son the AR-15 rifle used in the slaughter — was charged with involuntary manslaughter, two counts of second-degree murder, and eight counts of cruelty to children.

Both the father and son made their initial court appearances on Sept. 6 and did not enter a plea.

They are being held without bail, and are next scheduled to appear at Barrow County courthouse Dec. 4.

Relatives have claimed the boy had a troubled upbringing.

The alleged shooter’s mother has had multiple drug and domestic violence arrests, and her addiction ultimately cost her custody of Colt and her other children.

He lived at the time of the shooting with his father, who allegedly berate him and call him names to toughen him up, according to relatives.