Cassandra Tanner-Miller said she wants to spend her life making sure other parents don’t experience the horrific tragedy she went through when her 18-month-old son was murdered.

Tanner-Miller, 32, said the military and the judicial system failed to protect her and her family from her estranged husband, Christopher Michael Miller, a man she called a “monster” and a “murderer.”

She said her 35-year-old husband forcefully entered her home Saturday, viciously beat her and her 9-year-old daughter, Cameryn Tanner, and then shot her young son, Colton Michael Miller, nine times before turning the gun on himself.

“I’m going to spend the rest of my life making sure that I can get a law for Colton, so that he did not pass away in vain and no other mother mourns the loss of their baby because the dad murdered him,” Tanner-Miller said through tears.

Joliet police said they responded about 2:45 p.m. Saturday to the incident at Tanner-Miller’s residence on Buckingham Road.

Officers found Tanner-Miller and her daughter and they told the officers they heard what sounded like gunshots from the residence before officers arrived, police said.

Tanner-Miller said what happened was not a hostage situation.

“This was a trained killing machine who had a violent background,” she said of Miller.

Tanner-Miller said Miller was part of the Illinois National Guard and served in the Army for several years but was never deployed overseas.

The Illinois Army National Guard did not respond to messages about Miller’s service record Monday.

Tanner-Miller said her husband struggled with drug addiction and had mental health issues.

Tanner-Miller also said that he was charged Dec. 29, 2017, with aggravated battery in DuPage County after he “savagely” beat a man in a parking lot in Naperville.

She said that because she was technically considered a witness in that case, the judge ordered Miller not to threaten her or harm her.

On Saturday afternoon, while her son was napping, Tanner-Miller said, she noticed her husband on the back porch of her home. They had been living separately for about a year, she said.

Tanner-Miller said he was smiling and didn’t appear well.

Tanner-Miller said Miller forcefully opened the door to the porch and – with a smile on his face – said, “Are you all ready to die today?”

Tanner-Miller said he physically attacked her but she fought as hard as she could. She said she could hear Miller laughing as she slipped in and out of consciousness.

“I met the devil that day and they exist,” she said. “Evil exists and it was in my house.”

Tanner-Miller said he went to the stairs of her home, put Cameryn in a chokehold, bit her and pushed her away before heading for Colton. She said her daughter tried to fight Miller.

“She did everything that she could that day to protect her brother,” Tanner-Miller said of her daughter.

Tanner-Miller said she regained consciousness but was staggering and bleeding. She said she heard gunshots after she called for Cameryn to run toward her.

Tanner-Miller said her husband was a “murderer and that coward took his life afterward.”

Tanner-Miller said if someone gets into trouble with the law for aggressive behavior, they should undergo a psychiatric evaluation and police should remove weapons from their home. She said Miller received a notice from the state to relinquish his firearms after he was charged with aggravated battery.

“There needs to be a change and I’m speaking to all mothers and families out there, and fathers, that we cannot let these monsters roam our streets,” she said.

She said a protective order is only “a piece of paper.”

“When someone does something aggressive and they have a history of aggressive behavior and you’re trying to get away from them, they’re not going to let you go,” she said.

Amirrah Abou-Youssef, of the Groundwork Domestic Violence Program at Guardian Angel Community Services, said those who experience domestic violence can call the Groundwork program at 815-729-1228, which is a 24-hour, confidential number.