The judge started with a 30-year sentence for manslaughter. She reduced it to 20 years because the mother pleaded guilty. Then, she added 2 years for child cruelty.

In Hong Kong, manslaughter can lead to life in prison.

The boy, called Z, was found dead in his home on September 2, 2022. His mother had called the police to report his death. The boy was very underweight.

Z was only 1 meter tall and weighed 9.7 kilograms. This is about half the normal weight for his age.

An autopsy found 129 injuries on Z's body. There were signs of force-feeding, gagging, and violent rubbing.

Experts said Z had likely gone hungry for 61 to 91 days. His organs and muscles had become very weak.

The judge said the mother's limited education did not explain her actions. She had taken good care of her other children but not Z.

The judge called the killing 'a protracted, cold-blooded annihilation'. The mother had not acted in a moment of rage.

The mother had been convicted of drug possession in 2018. She had told a friend she did not like Z and later said she had beaten him to death.

Z had been in foster care as a baby. He returned to live with his mother in August 2020. Social workers visited him several times.

In June 2022, a social worker saw Z but found no visible injuries. The social worker thought the abuse had stopped.

The social worker's report led to the family being transferred to another welfare organization.

The new social worker found out that Z had missed many days of nursery school. The worker learned about Z's death from the news.

A doctor had already noted that Z's height and weight were not normal for his age. It is surprising that the social workers did not find anything.

The judge said it is hard to believe that Z's life could not have been saved.

The mother said she was very sorry for what she had done. She had neglected Z and did not seek medical help when she was pregnant.

The mother's three other children are now in foster care.

A new law in Hong Kong requires certain professionals to report suspected child abuse. This law came into effect in January 2026.

The law might have helped Z if it had been in place earlier. It requires professionals to report suspected abuse as soon as possible.

The case of Z's death has raised concerns about child abuse in Hong Kong. The new law is intended to help prevent such cases in the future.

The mother's sentence reflects the seriousness of her crime. The judge's comments highlighted the need for better protection of children.