(NewsNation) — The mother of a 12-year-old girl who fatally stabbed her 9-year-old brother in Tulsa, Oklahoma, is speaking out for the first time, telling NewsNation the incident appears to be the result of a “manic episode of some kind.”

April Lyda explained in an exclusive “CUOMO” interview Thursday what she says caused her daughter to act out in violence.

“From what we found, it looks like it was a medication issue, not anything else,” Lyda said. “It’s like a manic episode of some kind.”

The stabbing happened in January, when the Tulsa Police Department says the 12-year-old girl woke Lyda up and told her she had just stabbed her brother. The boy was taken to a hospital, where he died.

The girl was taken to the Family Center for Juvenile Justice, police said in the January news release.

Lyda said her daughter had recently stopped taking ADHD medication for the second time prior to the killing.

The 12-year-old was on medication for five years, but stopped when she began to be home-schooled. When she returned to public school the following year and her grades began to slip, she went back on medication at the recommendation of school and health professionals, Lyda said.

She then stopped taking the medication when she began to cut herself, Lyda said. She did not specify what medication her daughter was taking.

“She loved him and he loved her. She has no idea why she did it. She’s heartbroken and she feels very guilty, but she still doesn’t understand why she did it,” Lyda said. “She said it was like it wasn’t her, and the team of specialists working with her, they believe her after working with her for the last six months every day. I believe her, too, because I know my child, I know that wasn’t her.”

Police body camera footage shows the 12-year-old saying as much the night of the killing.

“I don’t know why I did it,” she tells responding officers, according to a Law&Crime report. “I’m so sorry, I don’t know what happened,” the girl says to her mother.

The girl was not exhibiting any violent or aggressive behavior in the days preceding the killing, Lyda said, but the family did become aware of comments she made to friends beforehand about having thoughts of stabbing her brother.

“Unfortunately they were maybe afraid to tell their parents or me,” Lyda said. “I had no idea that she was having those thoughts.”

Dr. Darcy Sterling, a licensed clinical social worker, said Thursday on “CUOMO” there are “pieces of this puzzle that are missing” and was skeptical that the medication was the only factor at play.

“I have never heard of a situation where a child just inadvertently does something like this (with) zero warning signs,” Sterling said. “The meds are not going to make somebody homicidal like that.”

Lyda said no charges have been filed, but “later on down the road,” there might be.

At the time of the killing, Tulsa Police Capt. Richard Meulenberg told KOKI-TV that “intent is going to be a key component that the court system will have to work out.”

“I want her to get whatever help she needs,” Lyda said. “She’s going to have a lot of hard time grieving and feeling guilty, so she’s going to need a lot of help in that aspect. … I eventually want her to come home when she is done with her treatment.”

Few additional details have been released about the case. The Tulsa District Attorney’s Office told The New York Post it couldn’t disclose any information about the case — including any possible charges — because of the girl’s age.

Florida prosecutor Dave Aronberg said charges could effectively be used as a way to mandate the girl remain in a treatment program.

“I think it’s important that prosecutors look at this closely to perhaps charge so that we make sure this girl at least gets the help that she needs,” Aronberg said.