The author of the bestselling memoir “A Child Called ‘It:’ One Child’s Courage to Survive” says allegations of child abuse against Connecticut stepmom Kimberly Sullivan are troubling. 

“That is attempted murder,” Dave Pelzer told Fox News Digital, adding details of the Sullivan case are “beyond sadness.”  

Sullivan, 56, was arrested March 12 in Waterbury, Connecticut, after her 32-year-old stepson set a fire at their house Feb. 27 to escape what authorities said were abusive conditions. He weighed just 68 pounds. 

As chronicled in his book, which has sold millions of copies and spent several years on The New York Times Best Sellers list, Pelzer was physically and emotionally abused by his mother from ages 4 to 12. 

‘MALNOURISHED MAN HELD CAPTIVE BY STEPMOM FOR DECADES SET FIRE TO HOME TO ESCAPE: ’I WANTED MY FREEDOM’

“I’ve worked a lot of cases — a lot of cases. This is severe. Extremely severe,” Pelzer said. “Because of the length of it and the fact, again, [the victim is] 5-foot-8 and 68 pounds. And I’m worried about his mental state.”

The Waterbury Police Department located Sullivan’s 32-year-old stepson at the home, where he admitted to setting the blaze. 

The man, who has not been named, was found emaciated and told police he had been confined in the home since age 11. He said he had never received medical or dental care.

“I wanted my freedom,” he told investigators. 

MAN DESCRIBES SHOCKING LIVING CONDITIONS HE ENDURED DURING 20-YEAR HOME CAPTIVITY: ‘UNIMAGINABLE’

According to an arrest warrant for Sullivan, the victim, identified as “Male Victim 1,” was held in a windowless 8-foot by 9-foot storage closet with no air conditioning or heat and without access to a bathroom for 20 years. He was kept inside the closet 22-24 hours per day. 

He was allowed two sandwiches and two small water bottles each day, one of which he would use for bathing. He disposed of his waste using water bottles and newspaper. 

Sullivan was arrested on charges of first-degree assault, second-degree kidnapping, first-degree unlawful restraint, cruelty to persons and first-degree reckless endangerment. 

She was released on $300,000 bail. 

UTAH MOMMY BLOGGER RUBY FRANKE’S POWER, PUBLIC IMAGE ALLOWED CHILD ABUSE TO GO ‘UNCHECKED’: EXPERT

Despite the fact the victim was sometimes allowed out of the house to let out the family dog and do chores, Pelzer said victims of extreme abuse do not run because they are conditioned by their parents into thinking that the abuse they face is normal. 

“I’ve got to tell you, when I went to court, when I was being made a permanent ward of the court, I was with my beautiful social worker. God bless her,” Pelzer said. “And I saw my mom right across the hallway, and I forgot I had done this, but I guess I wrote a note to my mom saying, ‘Dear mom, I’m so sorry about this.’

PARIS HILTON URGES HOUSE TO PASS ‘STOP INSTITUTIONAL CHILD ABUSE ACT’ AFTER SENATE’S UNANIMOUS APPROVAL

“I remember one time I was going to run away,” he said. “I think I was 6, and I had it all planned out. I stole an apple pie and brought it into the basement. They were gone for an afternoon for family affair or whatever, and I was about to run away. I thought, ‘Where am I going to go? Who’s going to take me in?’”

While there have been reports the Connecticut Department of Children and Families visited the Sullivan home in response to reports from the victim’s school, Pelzer explained that abusive parents often have a unique ability to manipulate authorities. 

Read Kimberly Sullivan’s arrest warrant: Mobile users click here

“We are shocked and saddened for the victim and at the unspeakable conditions he endured. The now adult victim has shown incredible strength and resilience during this time of healing, and our hearts go out to him,” the department said in a statement.

The department noted there are no records of visits to the Sullivan home on file because reports of neglect and abuse that are unsubstantiated are expunged from its system after five years.

Pelzer said he hopes a caring family member will support the victim, who will have limited state resources for recovery as an adult. 

Fox News Digital reached out to two of the victim’s sisters and Sullivan’s attorney.