The video footage was devastating: It showed his maid unleashing a kick to his 23-month-old daughter's left thigh.
The toddler toppled over from the force of the kick.
Mr Christopher Sun, 28, was stunned.
The first sign of trouble was when he saw scratch marks on his daughter's arms in May last year.
He had employed Indonesian Khaerun Nisa Selfitriya, 28, after the birth of his second child, as both he and his wife are working full-time.
Mr Sun is Khaerun's second employer.
When he confronted her about the scratch marks, she told him that his daughter got hurt in preschool.
The sales executive then made a trip to the school to find out more.
"They told me that it was unlikely that my daughter got hurt in school because she was adored by her friends and teachers," said Mr Sun.
He did not press the matter further after the school offered to check their closed-circuit television (CCTV) camera.
Concerned for his children's safety and suspicious, he installed a CCTV camera in his home.
To his horror, the footage showed Khaerun ill-treating his children in the living room of their four-room flat in Woodlands.
Mr Sun told The New Paper: "I was furious that she was daring enough to abuse my children.
"My wife and I have never once laid our hands on them like that."
Mr Sun added that his wife, who works as a beautician, was heartbroken and felt betrayed because she had treated Khaerun well throughout the five months she was living with the family.
"Two weeks before the incident, my wife took Khaerun and the children along with her to visit her parents in China," said Mr Sun, a Singaporean.
"My mother-in-law fed her well and even bought her new clothes."
During one of her weekly visits to check on her grandchildren, Mr Sun's mother told him that his flat was dusty and unkempt.
"The maid told us that she didn't know how to cook, so we told her to just help out with some household chores," said Mr Sun.
"After about five months into her employment, she became complacent, waking up late and taking naps in the middle of the day."
Mr Sun's next-door neighbour, Madam Rohanah, 58, described Khaerun as friendly and mild-mannered.
"We used to talk occasionally when I hung my laundry in the corridor and their front door was open," said the retiree.
"Sometimes I gave her some food to eat.
"I have never seen her scolding the children, so the news took me by surprise."
Mr Sun has since employed another maid, a Myanmar national, from another agency.
"I definitely didn't expect this to happen, but I know that I cannot have the mindset that all maids are like this," he said.
Just to be sure, he has installed two CCTV cameras in his flat and asked his parents to help monitor the household.
"My parents visit our flat every three to four days to check on my children," he said.
"On some weekends, my daughter sleeps over at their place. Hopefully, it'll lessen the burden on our new maid."
Maid jailed for ill-treating toddlers
She had lashed out at her employer's two toddlers, thinking that nobody would find out.
Last October, Indonesian maid Khaerun Nisa Selfitriya kicked Mr Christopher Sun's 21-month-old daughter and slapped his eight-month-old son's back multiple times.
But Khaerun, 28, did not know about the closed-circuit television (CCTV) camera in Mr Sun's four-room flat in Woodlands.
Yesterday, Khaerun was sentenced to four months' jail on two counts of ill-treating the children.
Deputy Public Prosecutor Kenneth Kee had asked for a jail sentence of at least four months because the minors were "defenceless, young toddlers" unable to voice their concerns to their parents.
Mr Sun, 28, had placed a hidden camera after finding scratch marks on his daughter's arms in May, the month Khaerun started working for the family.
CCTV footage showed Khaerun, a native of Lombok, Indonesia, feeding the children in the living room at about 6.50pm on Oct 14.
She suddenly kicked Mr Sun's daughter on her left thigh after the toddler refused to finish her food and started to vomit and cry.
The kick caused the girl to fall on her right side and hit her head on the floor.
About 10 minutes earlier, her younger sibling had cried during feeding.
Khaerun, a mother of four girls, then shouted "no" and slapped the boy's back multiple times with her left hand.
Her lawyer, Mr Nasser Ismail, said Khaerun "had reached a breaking point where she lost her mind on that fateful day".
A combination of stress and depression had triggered her ill-treatment of the children, he said during mitigation.
He added: "Khaerun never intended nor actually harmed the children. She is truly remorseful for her folly."
At the end of the court proceedings, a cheerful Khaerun was heard saying, "Thank you, Ma'am," to District Judge Michelle Yap.
A Filipino maid was jailed two weeks for hurting a baby.
While attending to her employer's crying baby girl at around 1.30am on Feb 21, she had pulled the seven-month-old's right hand forcefully, causing a fracture.
She admitted to being forceful with the baby as "she was agitated and tired".
Indonesian maid Annisa was jailed three years for lacing breast milk meant for her employer's two-month-old baby with eucalyptus oil.
She had meant to scare and anger her employer into sending her back to Indonesia.
Her crime was discovered in August 2014, when her employer noticed a pungent smell coming from one of the bags of breast milk she had kept in the freezer.
The employer later discovered among Annisa's belongings a bottle of eucalyptus oil.
A Myanmar maid was jailed three months for flinging a knife at her employer's daughter, aged 4.
The maid's action in February that year was caught on a hidden CCTV camera.
She was seen slapping the girl on the head, hitting her arm and pulling her hair.
The maid took a knife with a 20cm-long blade from the kitchen after being frustrated trying to get the girl to eat.
This article was first published on Jan 5, 2016.
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