The father is Singaporean, the mother Mongolian and the boy was just one year old when he came here with his parents from London, ostensibly for a short visit.
Once in Singapore, the boy's father served divorce papers on his mother and applied to restrain her from taking her son back.
Thus began a stormy custody battle that has stretched four years and seen both parents spend time in jail as they tried to wrest custody of the child. It reached an important landmark this week when the High Court ordered that the child be returned to London within 28 days to reunite with his mother.
The boy, called M in court papers to protect his identity, has been living here for the past four years with his Singaporean grandparents. More recently, he has been joined by his father, who fled England last year to return here.
Judicial Commissioner Valerie Thean, in decision grounds on Tuesday, made clear the court's main consideration was the child's welfare - and this would be best served if he were reunited with his mother so that she could care for him daily.
The child's father, 40, is to return him to his 34-year-old mother on the Family Justice Courts premises.
While the couple will have joint custody of the boy, he will be in his mother's care in London. The father, however, will have daily access to him over Skype.
How the saga unfolded
July 2012: The boy is born in London. His father and mother, who were married in June 2011, bring the boy to Singapore to be cared for by his paternal grandparents in July 2013, and leave a month later for London.
January 2014: The boy's mother travels to Singapore with the husband, not knowing that he has begun divorce proceedings. An English judge grants the mother's application for an order for the son to be returned, and also impounds the husband's passport.
March 2014: An English judge rejects the husband's appeal and orders him to return the son within a month. The boy's grandparents apply to be appointed his legal guardians in Singapore.
April 2014: The boy's father is jailed for 18 months by a British court for failing to return the son. Two months later, the father wins an appeal against the sentence and is released after nine weeks. He wins a claim for damages for unlawful detention in April this year.
August 2014: The boy's mother engages the assistance of an international outfit in an attempted abduction. She pleads guilty in September 2014 to immigration offences and is sentenced to 10 weeks' jail.
May 2016: A Singapore court issues an order mirroring that of the English court on the boy's return. The mother travels to Singapore to take her son back to England, but fails due to the grandparents' move to appeal.
September 2016: The boy's father absconds from England to Singapore by lying that he had lost his passport. He was sentenced to three weeks' jail in May this year.
August 2017: Singapore's High Court awards joint custody to both parents, care and control to the mother, and reasonable access to the father.
"The need to ensure a stable care environment does not override the need for M to be reunited with his mother," added the judge.
The boy is autistic. His father and grandparents say they provide him with ample care and claim that his mother does not love him.
To help suss out the child's needs and how they could best be met, the judge appointed two experts to observe M. The boy's affection for his mother shone through despite long years of separation. "I really also love you and I miss you," he told her over Skype.
The judge also noted that when M's mother visited him last year, pictures showed he was thrilled to be in her arms and by her side.
She did not find evidence of such intimacy in M's interaction with his father, though she noted that his father had gone out of his way to address the child's needs - playing mathematical games with him and enrolling him in a therapy centre.
And while M's grandparents had cared for him for four years, she pointed out: "A child's grandparents are no substitute for the personal love and care of his parents."
A child should enjoy the support of both parents, she said. But it was clear to her that the boy's father and grandparents had no intention of involving his mother in his life. They did not tell her about his autism and have possibly given him the impression that London is a place filled with "bad people".
The judge said that if M remained in his father's household, he would likely be kept away from his mother. In contrast, the mother appeared to recognise that the father ought to play a role in M's life. She was also capable of "meeting his emotional and developmental needs".
The road to the High Court judgment has been peppered with anguish for both parents.
The boy's mother made the news in 2014 when she entered Singapore illegally by boat to try to snatch her son away from his grandparents. She was jailed for 10 weeks and deported to London, where she won her battle to get the custody issue settled in a London court.
The father was wrongly jailed for nine weeks in England in 2014 for failing to produce the boy in court. He will be compensated for that.
Yesterday, he said that he would appeal against the latest verdict.
The mother, in an e-mail, thanked her lawyer Koh Tien Hua and said: "After all these years, my beautiful boy will finally be coming home. I cannot wait to hug him... kiss him... show him how much he is loved."
•Additional reporting by Melody Zaccheus