Eugene Quatron McCoy had fought with his mother since he was a young boy.

“He always just stayed angry with his mom,” said Eugene McCoy, father of the 21-year-old man charged with stabbing to death his mother, Sheila Irons, and his 11-year-old half-brother Zion McPherson and 8-year-old half-sister Chasity McPherson. He also is charged with aggravated assault on his 17-year-old sister, Candice McCoy.

“She was always telling him to get a job. She tried to push him to have a little drive and motivation,” McCoy told The Atlanta Journal-Constitution Thursday.

His only son, whom he called Quatron, is being held without bond in DeKalb County’s jail on three charges of murder and one of aggravated assault. His other child, Candice, is in the intensive care unit of an Atlanta hospital, recovering from the stab wounds she suffered before escaping the house on Rockland Road in Lithonia and running to a nearby house for help.

McCoy has spoken to both his children since the vicious, bloody attack at the brick ranch house near Lithonia.

McCoy said Candice “asked for her mama yesterday. I said ‘you’ll see her later.’” She knows her half-siblings are gone but she doesn't seem to understand that her 45-year-old mother also is dead, McCoy said.

Quatron told his father that he and his mother “were arguing and it got out of hand. She wanted him to get on disability and take medicine,” McCoy said. “He didn’t want to. He said he ain’t stupid.”

McCoy, who lives in South Georgia, didn’t know of past violence between mother and son, only the frequent arguments, until the stabbings Sunday night. McCoy said Irons would tell her son he could not stay with her so he would sleep in his car.

“I never seen him be violent,” McCoy said. “But she [Irons] said he's hit Candice before.”

Quatron pleaded guilty in December to family violence battery, disorderly conduct and criminal trespass for hitting his sister. He was sentenced to time served for the 14 days he had already spent in jail, and sentenced to just under three years on probation. The judge also said in the Dec. 8 order that Quatron could have no contact with his sister and he could not return to the residence.

Earlier last year McCoy also pleaded guilty to violating the two restraining orders his mother had secured. In September, the second time he was in court for violating a protective order, the judge’s sentence included the instruction that he was to “have no violent contact w/ Sheila Irons – 12 months.”

McCoy said Irons had let Quatron move back in but gave him 30 days to find a job. He did not find work by her deadline so his mother told him he had to move, and that started the argument Sunday night.

“He said he loved his sister,” McCoy said of his conversation with his son.

But he claimed he stabbed his family members in self-defense, McCoy said.

“He just felt like they were going to kill him,” McCoy said.

Some of Quatron problems could be attributed to his bipolar condition and that he stopped taking medication several years ago, McCoy said. His condition worsened four or five years ago after he was seriously injured when the car he was in flipped while going 120 mph.

Still, McCoy said, he didn’t have trouble with Quatron like Irons did.

“He was very disciplined with me,” McCoy said. “He had some fear of me. He just didn’t respect her. She always got on him.”

Quatron was born five years after his parents married in Rochester, N.Y.

He was 13 and starting the sixth grade when his mother, sister, and half-siblings moved to Georgia. For three months, Quatron and Candice lived with their father in Hazlehurst while their mother, a cosmetologist, found a place to live.

“He had problems then,” McCoy said. “I had to stay on him because he would forget things. It was like he was in another world.”

McCoy said his son and daughter were opposites. Quatron failed at school and stopped going when he was around 14. Candice got A's on her report card and will have her choice of three colleges that have accepted her. Quatron was quiet and angry, and Candice was outgoing and happy, McCoy said.

“He had all F's and wasn’t paying attention. He was put in the slow classes,” McCoy said.

His grades improved after moving in temporarily with his father, McCoy said. “He was almost honor roll. I was real tight on him.”

But social services removed the two children after Quatron told his mother that his father “had kicked him in his behind and she called police,” said McCoy.

Quatron’s behavior got worse after he was seriously injured in a car crash in 2006 or 2007. The car was traveling at 120 mph when it flipped over. Quatron was a passenger.

And Quatron’s grandmother reported that her grandson “was picking on little children and saying was going to kill them” on one of his visits to her house in New York.

“I don’t know what was going on in his mind,” McCoy said. “He resented that they kept locking him up and she [his mother] kept putting him out."