In what the prosecution described as "one of the saddest cases of child abuse", a 34-year-old woman was sentenced to eight years in jail after punishing her four-year-old so badly that he died. The boy's offence in 2014 was not reciting the numbers 11 to 18 in Malay properly.

The response from Noraidah Mohd Yussof was to push him repeatedly - causing him to hit his head on the floor - step on him, and grab him by the neck until he was lifted off the ground against the wall.

Four days later, despite emergency surgery to remove a part of his skull to allow swelling in his brain to expand, Mohammad Airyl Amirul Haziq Mohamed Ariff died.

In sentencing Noraidah, Justice Lee Seiu Kin rejected the defence's contention that she has Asperger's syndrome - an autism-like disorder that affects how a person interacts with others.

Instead, he accepted the evidence of prosecution psychiatrist Subhash Gupta that she has "personality aberrations" - including a very low tolerance for frustration, a tendency to act impulsively and marked proneness to blame others.

The prosecution had sought at least 12 years' jail, while the defence argued for less than 10 years after the unemployed woman, who had initially been charged with murder, admitted to six instances of physical abuse - one in March 2012 and five between June and August 2014 - at her Eunos flat.

The court heard that in 2012, when the boy was two, Noraidah, became irritated when teaching him the alphabet. She pushed him and stepped on his ribs when he fell. She also twisted his hand when he scribbled on a sofa. She later took him to hospital, where he was found with fractures to an elbow, calf and four ribs, as well as multiple bruises.

The Ministry of Social and Family Development placed the boy in the care of her brother and sister-in- law. He was later returned to Noraidah's care.

On Aug 1, 2014, she pushed him for not reciting numbers properly. He got up and continued reciting as he followed her around the flat, but she continued to shove him.

She then told him to get ready as she was going to fetch his sister from school. As Noraidah took a shower, he stood outside the bathroom, still reciting.

Angry that he was mumbling numbers instead of getting ready, she held him by the neck until he was lifted off the ground against the wall. He started gasping for air and later stopped moving.

Recently, a 41-year-old mother was jailed 11 years for abusing her two-year-old son. The woman's 46-year-old boyfriend was given 10 years' jail and 12 strokes of the cane.

The couple had kicked and slapped the boy almost daily, forced him to eat spoonfuls of dried chilli and stamped on his chest.