SINGAPORE - A mother of two died from head injuries following a fight with her sons, one of whom is autistic while the other suffers from major depression, a coroner's court heard.

During the inquiry on Tuesday (April 26) into the 52-year-old woman's death, it was revealed that the elder son, who was 21 years old at the time, suspected his mother of having an affair and a brawl broke out when he demanded to see her phone.

Both sons pushed her during the fight on Aug 16, 2019, causing her head to hit the wall twice. She later died from head injuries in Khoo Teck Puat Hospital (KTPH).

There is a gag order to protect all of their identities, and the next of kin were not in court on Tuesday.

Assistant Superintendent of Police (ASP) Mahathir Mohamad, the investigating officer in the case, was the sole witness called to the stand during the inquiry. He told the court that the woman's husband, 55, is a bus driver and had left for work at 4.30am on the day of the incident.

The woman was the main caretaker for her younger son, then 17, who has autism. She worked as a sales assistant on the weekends.

The younger son was diagnosed with autism disorder when he was four and found to be minimally verbally and intellectually disabled.

The court heard that the older brother, who was doing his national service at the time, had suspected that his mother was having an affair two months before her death as she had begun sleeping in the living room of their three-room flat, and would talk on the phone softly.

On the day of the incident, at about 6am, he eavesdropped on her conversation, asked her who she was talking to and demanded to see her phone.

ASP Mahathir said a fight broke out and the elder son slapped and punched his mother in her face.

During the struggle, he snatched the phone and threw it on the floor, and his mother bit his arm to stop him from getting her phone. He also pushed her, causing her to hit her head against the wall near their TV console.

The younger son entered the living room and hit his brother on the shoulder.

Their mother advanced towards the pair and, in the struggle, the younger son pushed her and she hit her head against the wall for a second time.

She took two steps forward, collapsed, had seizures and vomited, ASP Mahathir said.

The elder son called his friend and tried to get an ambulance.

The woman was unresponsive when the Singapore Civil Defence Force arrived at the unit at about 6.25am and found her lying on the floor on her back.

The elder son followed the ambulance to KTPH while his friend watched over his younger brother.

The elder brother was arrested later in the afternoon for a rash act causing grievous hurt. He had earlier admitted to paramedics that he had punched his mother and pushed her, causing her head to hit a wall.

The mother was pronounced dead on Aug 24, 2019.

An autopsy report found that the cause of death was a head injury consistent with a direct blow or impact with a hard surface. It could not conclude which head injury was the lethal one.

The mother's phone was seized but it was broken and the police were not able to find any information on it.

The elder son was found to have major depression that led to poor judgment and "likely served as a contributory factor to the offence". He was given 24 months' conditional warning.

An Institute of Mental Health report found that he had grown increasingly upset about his mother’s alleged affair and displayed an acute stress reaction. He was prescribed antidepressants.

The younger son, who was unable to attend special education programmes in school after he turned 18, is currently in a home. He was deemed not fit to plead in court, nor likely to be able to do so in the future. No legal action was taken against him.

The court heard that the younger son is not allowed out of the home without supervision, and his father and brother visit him weekly. 

State Coroner Adam Nakhoda will deliver his written findings on July 1.