There were red flags earlier this year in the behavior of an Oklahoma mother who killed her three children and herself, according to one of the young victims’ fathers.

Brandy McCaslin, 39, shot and killed her three kids — 11-year-old Noe, 6-year-old Bryce and 9-month-old Billy — then turned the gun on herself on July 20 following a police standoff at her Verdigris home.

The father of youngest child is speaking out about warning signs regarding McCaslin’s alleged mental state in the months leading up to the slayings.

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“There was an incident in January where Brandy had tried to commit suicide, and they actually had to wrestle the gun out of her hand, her nephew did,” Billy Jacobson, the baby’s father, told Fox 23.

Jacobson said he immediately filed and was granted emergency custody of the child he shared with McCaslin.

“Everything was good for about a month,” Jacobson told the outlet. “She did a little treatment, and they decided to give her back supervised visitation, which I was hesitant of that as well, I was scared that there wasn’t anything changed.”

Verdigris Police Chief Jack Shackelford told Tulsa World that on July 20, a woman brought one of McCaslin’s three kids to the Verdigris residence for a supervised visit, along with two other children.

McCaslin then threatened the woman with a gun, trapped her and the two other kids in the garage and then barricaded herself and her three children inside the home.

The woman who was locked in the garage then set off a Roman candle firework through a broken window in the garage to seek help, which drew authorities who helped the woman and the two kids escape.

“I had two grandbabies there that could have been gone,” Janet Whisman, the grandmother of both Bryce and one of the kids that was held in the garage who escaped, told Fox 23. “I’m just very lucky that the lady in the garage, my daughter–in-law, was smart enough to try to get help. She’s the one blowing the Roman candle out the window.”

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Oklahoma State Bureau of Investigation Public Information Manager Hunter McKee told Tulsa World that a standoff between the mother and police began at around 4 p.m., after a Verdigris police officer saw the firework set off through the garage and “knew there was something wrong.”

Police made efforts to negotiate with McCaslin, prompting the standoff to ensue “for the next three hours,” according to the Oklahoma State Bureau of Investigation.

“After no response, officers made entry into the home where they found McCaslin, along with her three children, dead inside,” the bureau said in a July 20 statement.

Police determined the 39-year-old shot the three kids, before turning the gun on herself.

“There was nothing I could do, and I basically watched my son fade from my hands, because I knew something bad was going to happen and no one would help us,” Jacobson said of McCaslin’s supervised visits with his son.

The family members who spoke with Fox 23 said they are upset with a system that allegedly neglected to protect kids who were under the care of a mom who they say was suicidal.

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Josh Kerr, the pastor at First Presbyterian church in Claremore and a long-time acquaintance of McCaslin, told Oklahoma City-based TV station KWTV that the woman had been struggling with mental health problems.

“Lots of tragedy, suicides in the family, drug use, all the brokenness we see in our communities all the time,” Kerr said.

Jacobson told Fox 23 he wants laws to better protect children in cases like this.

“We got to have some checks and balances and some accountability when it comes to mental health in this state, because as it sits now, it cost my baby his life and it cost two other, two kids that I consider my children, their lives too,” he said.