He was first exposed to pornography at the age of 12 while surfing the internet.

Driven by his urges, the boy tried various sexual acts on his younger sister, including sexually penetrating her in 2013.

Despite receiving counselling over the incidents, the boy molested his sister again three years later. Their mother lodged a police report against the boy in April last year.

The boy, who cannot be named to protect the identity of his sister, pleaded guilty to one count of sexually penetrating a minor under 16 and one count of using criminal force to outrage the modesty of his sister. He is now 16 years old, while his sister turned 15 in April.

Three counts of sexual penetrating a minor under 16 and three counts of molest will be taken into consideration when the boy is sentenced.

The court heard that the boy was disgusted when he chanced upon online pornography for the first time while in his flat. However, he became interested in it and began masturbating regularly. He eventually felt the urge to try the what he saw on pornographic websites.

“He went on to commit sexual acts against the victim since she was in close proximity to him, and also because he was confident that she would not disclose what he did to her to others,” said Deputy Public Prosecutor Raja Mohan.

Sometime in September 2013, while alone in the flat with his sister, the boy, then 12, was sexually aroused after watching a television show involving a bedroom scene. He called his sister, then 10, to the room and told her that he wanted to try something with her. He threatened to tell their parents about her mobile phone usage if she did not comply.

She stripped, as instructed by her brother, while the boy removed his shorts. The boy proceeded to sexually assault his sister and stopped only after his sister complained of pain and discomfort. He told his sister to leave the room while he masturbated.

When their parents discovered that the boy had molested his sister on several occasions, they sent the two to counselling in 2014. No police report was lodged then.

The parents arranged for the boy to move in with his grandparents to separate him from his sister.

After half a year of counselling, the boy was allowed to move back to his flat. House rules were implemented to prevent the boy from repeating his offences and the parents also agreed to supervise him closely.

However, the boy did not stop molesting his sister. He went on to touch her on at least four different occasions in 2016.

In June 2016, the family moved into the home of the children’s maternal grandparents after the parents sold the flat.

A month later, the boy started watching pornography as he was stressed over his studies. Acting on a strong sexual urge one night, the boy told the girl to accompany him to his bedroom. While seated on his bed, he molested his sister.

The mother found out about the incident and told the counsellor about it. The matter was referred to the Ministry of Social and Family Development’s Child Protective Services. The parents lodged a police report on 3 April last year.

The boy will be sentenced on 9 July.