SINGAPORE - A 59-year-old man was sentenced to 20 years' jail on Monday (May 14) for a string of sexual offences against his employer's granddaughter, from when she was seven years old.

He was convicted of three counts of digital penetration without her consent while another nine charges - including committing obscene acts with a child and digital penetration - were taken into consideration.

The High Court heard that the man had been employed by the girl's father since 2006 as a delivery driver for the family's restaurant, which was owned by the girl's paternal grandfather.

The man bought sweets and toys for the girl, now nine, and her siblings and was exceptionally close with her, to the point where she described him as her "best friend".

The girl appeared to "lack attention from her parents" and was very happy whenever the man visited her. The man and the girl cannot be named due to a gag order.

In September 2015, when the girl was at the family's restaurant with her grandparents, the man took her to an office rest area that he knew had no surveillance cameras.

The girl sat on his lap and he then sexually assaulted her. She displayed discomfort and the man stopped and told her: "Don't tell anyone, this is our secret."

He committed similar offences over the next few months in the office rest area. On one occasion, he promised to buy the girl fastfood and she followed him into the delivery van he drove. Inside the parked van, the man committed an obscene act on the girl.

In June 2016, the girl's father fell out with her grandfather. The girl and her immediate family moved out of the grandfather's house to live separately.

The grandfather often asked the man to bring household items and food to the girl's home. He would sexually assault her during these visits.

On one occasion he did so while the girl's half-sister, a toddler, was in the same room watching television.

On Dec 5, 2016, the man went to the victim's home to deliver a baby cot and he sat down on the sofa with the girl, who was wearing a T-shirt and long tights.

The family maid was seated at the dining table, facing away from the sofa. The man showed the girl a pornographic video and then sexually assaulted her. The maid then turned and noticed what he was doing and heard her say: "Uncle, stop it."

When the man left, the maid asked the girl what happened and she began crying and recounting the experience. The maid reported the incident to the victim's grandfather. The family eventually reported the case to the police.

The girl explained that she did not tell anyone about the sexual acts as she was scared that the man "wouldn't want her anymore" as he was usually very nice to her.

Deputy Public Prosecutor David Khoo asked for a sentence of 28 years, noting that the man had betrayed the trust of his long-time employers and that the girl was an "exceptionally vulnerable victim" due to her young age.

Mr Khoo added that the man had tried to morally corrupt the girl by showing her pornographic videos and noted the element of pre-meditation due to how he "isolated the victim for the opportune time to come" for the acts.

The man's lawyer, Mr Wee Hong Shern, said his client was lonely and lacked a conjugal relationship with his estranged wife.

This was dismissed by Justice Woo Bih Li as "not a mitigating factor".

The man's sentence will start from his date in remand - Dec 12, 2016. He escaped being sentenced to caning because he is over 50.