After all, it was their father Rimoni Muliaga, who took her life at their home in Melbourne's outer west.
But two-and-a-half years on, their son showed compassion and care as Muliaga faced a pre-sentence hearing in the Victorian Supreme Court.
"Please tell my dad he doesn't have to worry about us and we are thriving and serving the Lord, just like he would want," the teenager said in a statement read by senior crown prosecutor Patrick Bourke KC.
"I forgive him but I will never forget what he did."
Muliaga, 44, stabbed Lise to death in their Melton South backyard in September 2023 - months after they had moved from New Zealand and after accusing her of cheating on him with his brother.
But he denied he was guilty of murder and took the case to trial, claiming his diagnosed intellectual disability and depressive disorder impacted his reasoning.
A jury rejected those claims, convicting him of murder in December after four days of deliberations.
Eight victim impact statements were read to the court as Muliaga faced a pre-sentence hearing on Friday.
Five came from the children he shared with Lise, ranging in age from seven to 16.
Muliaga blinked away tears as one of his young daughters described her difficulty sleeping because she kept thinking about the murder.
"I was having a bad dream," the statement read.
"Mum went to heaven and dad went to prison alone. That made me sad."
Another one of the children drew a picture depicting his mother in heaven with God and his father in jail, while another child illustrated a bloodied woman lying on the ground.
The 16-year-old son told the court the past few years had been traumatic but it made him mature and he was motivated to become a father figure to his younger siblings.
"I honestly just want to live life to the fullest," he said.
Muliaga's brother Daniel and sister-in-law Marama also provided statements to the court, with Marama showing grace.
"I want you to know I forgive you for the mess you have made," she said.
"I pray for your healing for your sake and your beautiful kids."
Defence barrister Michael McGrath accepted it was an objectively grave case, given the victim was Muliaga's wife and he used a weapon.
But Muliaga showed remorse and his moral culpability should be reduced due to his intellectual disability and depression, Mr McGrath said.
He had limited capacity to self-regulate his emotions and the morbid jealousy he experienced at the time of the murder was a feature of his conditions, the barrister said.
Mr Bourke argued the jealousy was separate from Muliaga's diagnoses and while his time in custody would be more difficult, his moral culpability should not be significantly moderated.
Justice James Gorton will sentence Muliaga at a later date.
1800 RESPECT (1800 737 732)
Lifeline 13 11 14
Men's Referral Service 1300 766 491
31°C