Three minutes into strangling his pregnant wife with a towel to "shut her up" for belittling him, Teo Ghim Heng decided to kill her, a court heard.
As Madam Choong Pei Shan struggled for her life, he allegedly told her: "Shan, you got to let go already, I owe a lot of money. If you struggle, you will suffer."
After making sure she was dead, Teo is believed to have asked his four-year-old daughter to sit on his lap. "Don't be scared, Papa is here," he told her.
The girl cried as he allegedly tightened the towel around her neck. "Go find your mummy first. Papa will come soon," he told her.
Teo's chilling account of how he allegedly killed his wife and child, told to Dr Derrick Yeo of the Institute of Mental Health, emerged in court when the psychiatrist took the stand yesterday, the third day of Teo's murder trial.
The 43-year-old faces two counts of murder for strangling Madam Choong, 39, and the couple's daughter, Zi Ning, at their Woodlands flat on Jan 20, 2017.
Teo is said to have spent a week in the flat with the bodies and burned them before the deaths were discovered on Jan 28, 2017 - the first day of Chinese New Year - after Madam Choong's family called the police.
Dr Yeo, who saw Teo six times and interviewed his family members and co-workers, concluded that the former property agent was not suffering from any mental disorder when he allegedly committed the murders.
The psychiatrist said Teo's behaviour was logical, goal-directed and showed planning.
On the morning of Jan 20, 2017, Teo and Madam Choong quarrelled after she questioned why he had changed Zi Ning out of her school uniform.
He was able to make objective choices and consider alternatives to his behaviour. His action to kill his wife was not something that was out of his control.
DR DERRICK YEO of the Institute of Mental Health, on suspect Teo Ghim Heng.
When Teo said Zi Ning could be chased out of school as he had not paid her fees for two months, Madam Choong mocked him in front of their daughter, he said.
Teo said he was angered when his wife called him useless, and told her that she should not have married him. He allegedly went to the bathroom to get a towel, looped it around his wife's neck and pulled. Three minutes in, he decided to kill her and their daughter, and then commit suicide to "reunite the family".
Teo, who was mired in debt, told Dr Yeo that he decided to end all their lives because he did not want them to be hounded by creditors.
Dr Yeo said: "He was able to make objective choices and consider alternatives to his behaviour. His action to kill his wife was not something that was out of his control."
The psychiatrist said that when Teo told his wife to "let go", he was trying to convince her, and justify to himself, that ending their lives was the correct decision.
Teo also told Dr Yeo that he had killed Zi Ning because he reasoned that nobody else could give her the same level of care that he and his wife had.
After allegedly killing his wife and daughter, Teo tried to slash his wrist, but the cut was superficial. He also downed Panadol tablets and drank diluted insecticide.
Dr Yeo said: "He wanted to die on his own terms. Many of the attempts were either too painful, too difficult or not successful." This showed Teo was in full cognisant control of his actions, he added.
Teo wrote four suicide notes, including instructions for his wife's mobile phone - which contained photos and videos of Zi Ning - to be handed over to the girl's grandparents, as well as instructions for the division of the couple's assets.
This showed planning and forward thinking, said Dr Yeo.
The court also heard that days after he was arrested for the double murder, Teo told a Changi General Hospital (CGH) psychiatrist that he had "no regrets".
But Teo, who was treated at CGH for Panadol overdose, added that his only regret was that he had to take the life of his innocent young daughter.
The trial continues today.