The Japanese parliament has approved a change to a decades-old law, which will allow divorced couples to share custody of their children from 2026.
Traditionally, custody is granted to a single parent who is then able to completely cut off the other parent's access to their children.
Until Friday, Japan was the only G7 country that did not recognise the legal concept of joint custody.
Most divorces in Japan happen through "consent divorce" - where both parties sign a paper and mutually end a marriage.
In this scenario, lawyers say, the couple is free to decide custody and visitation arrangements. But if the two parties go to court, the judge awards custody to one parent.
This system has drawn criticism from divorced parents who say they have been estranged from their children as a result.
Minako Sato* is one of them.
When Ms Sato moved to her elderly mother's house to help out for a couple of months, she and her ex-husband agreed he'd bring her then 10-year-old son and five-year-old daughter to visit on weekends.
This arrangement continued for about a month and a half. But Ms Sato said she noticed that her former husband had changed - he was quieter and more distant.
"He stopped talking to me when he brought the kids to my mother's house," she said.
"At first I thought he was tired from driving. I didn't understand what was happening."
Then he told her he would no longer bring the kids to see her every weekend, claiming his mother called her a bad influence.
'Whoever takes the child gets custody'
"He said if I got any closer to the (family) home he'd call the police. I was afraid to go near it... (in case) he was violent or told lies to the police (about me)."
She tried calling the house - which her husband and children shared with her mother-in-law - but her calls were blocked. So in a desperate bid to see her daughter, she decided to show up anyway.
"I went to talk to my mother-in-law - I thought maybe she could talk to him to bring me back home."
Her mother-in-law called the police instead.
"Five or six policemen came. They said they wouldn't let me go unless I went to the station with them." Ms Sato said.
She was there for three hours with her daughter who got in to the police car with her.
This would be the longest time she'd spend with her daughter for years - before her estranged husband and his lawyer came to pick the child up.
"In the end the police officer said he was sorry but he couldn't do anything to help me."
After two years of being separated from her children, Ms Sato learnt her ex-husband had been awarded sole custody of the children.
"I knew by then that whoever takes the child gets custody," she said. "I knew it was coming."
Akira Ueno, a lawyer who specialises in parental abduction cases told the OceanNewsUK that this system dates back to before the second world war, based on the idea that children were "the property of the household", with the head of the household being a man.
"So if the wife gets divorced, she ends up being kicked out of the house while the child is kept with the father," Mr Ueno explains.
This later changed as women mainly become the primary caregivers of their children - with sole custody now going to the mother in most cases.
Last year, the laws were once again thrown in into the spotlight when Japanese table tennis star Ai Fukuhara was accused by her ex-husband of abducting their son.
Chiang Hung-Chieh, a Taiwanese table tennis player, said they had filed for divorce several years ago, with both reportedly agreeing to joint custody while in Taiwan.
But after she returned to Japan with their son, she cut off contact with Chiang, refusing to bring their son back to Taiwan. Earlier this year, duo announced they had come to a settlement - almost two years later.
But not everyone is happy about the new joint custody bill.
Some women's rights advocates say the new bill would force women who have accused their husbands of domestic violence to maintain ties with them.
"If you introduce the joint custody system, victims of domestic violence and children victimised by abuse will be under the control of the abuser. They can't escape," said lawyer Harumi Okamura.
Ms Okamura has had long experience in cases where women have taken their children and fled domestic violence and abusive marriages. She adds that those women feel they can only raise their children if they are free of the abusive partner.
But other lawyers have told the OceanNewsUK joint custody and domestic abuse should not be conflated.
"Dear Mom, How are you? I haven't seen you in years'
One and a half years through their divorce proceedings, Ms Sato found out that her two children had moved out of their family home.
She went online and found the house had been put up for sale.
"One day, I passed by and there was nothing. No car, no bicycles, nothing. I didn't know what to think. I didn't know where they went," she said.
Ms Sato said she contacted the police to report her children had been abducted but all they came back with was to say that her children were ok and were with their father and that her ex-husband didn't wish her to know where they were so they couldn't tell her.
"I don't have a restraining order against me. Legally, I should be able to see my children. I should be able to know where they're living." She said.
If a divorce dispute between parents continues for longer than a year, and the child consistently resides with one parent, this becomes a significant factor in the judge's decision on who gets custody, explains Mr Ueno.
"There's an advantage to whoever takes the child first," Mr Ueno said.
While Japan's criminal law has a clear penal code for "abduction of a minor" - the interpretation becomes a lot less clear when it comes to a parent taking their own child. Essentially, lawyers say, the authorities don't treat it as abduction.
"In Japan this is known as 'going estranged with children' or living separately with children - and it's tolerated." Mr Ueno said.
"The police don't take action, saying it's a matter between spouses. They don't intervene. It's a cultural norm in Japan."
In Japan, visitation rights are also not a legal right and are left to the discretion of a judge.
For Ms Sato, her first attempt to gain visitation to her children failed after a judge refused her claim on the basis that there was a deep dispute between her and her soon to be ex-husband.
Ms Okamura explains that in most cases, judges will only grant visitation if they determine it to be beneficial to the child. And when and if these meetings are granted, they happen under supervision.
After three-and-a-half years of being completely cut off from her children , Ms Sato was finally granted visitation with her children in August last year.
"I'd been trying to see my children for three years," she said, while in tears. " I was so tired by then."
The first meeting was a trial visitation - Ms Sato, her son and daughter were in the same room for the first time in years - albeit in court and under court supervision.
She was given 30 minutes to talk to them and was told she wasn't allowed to ask anything specific about their lives, where they lived, where they went to school or their friend's names.
She was not given a specific reason as to why she had to keep to "limited questions", but adds that she heard that other divorced parents were told similar things.
"My daughter was very quiet. It'd been three-and-a-half years so I think she was shy. But she said she'd been wanting to see me and that she loved me."
Her daughter also showed her a letter, which read: Dear Mom, How are you? I am worried because I haven't seen you for four to three years. I have become a third grader and I have lots of friends. I love you and I want to see you soon!"
Ms Sato smiles when she talks about her son, now a teenager.
"I asked him 'Is that you?' three or four times. Because he'd grown so much," she said. "He's much taller than me now."
If there had been a joint custody system in Japan, "none of this would've happened", she adds.
She says she is hopeful that the bill will eventually help eliminate parental abduction cases, but Mr Ueno is less optimistic.
He is doubtful that authorities will actually act against those who abduct their children, adding that there is still very little detail about how the joint custody system will actually be enforced.
"Frankly speaking, I think it's 'bare bones'- a bill without substance", he says. "How can you enforce joint custody when there's no infrastructure to do so?"
Back in Tokyo, Ms Sato has finally been granted regular visits with her children. She now gets to see them once a month.
She doesn't know much about their lives she says, but she hopes to make up for lost time.
"At least I'm getting the chance to see my children", she says, smiling through tears.
