Like most teenage boys Dylan* heads straight to the fridge the moment he gets home from school. At 16, he's also at that stage where he seems incapable of hanging up his blazer.

'I didn't have time, Mum!' he protests – a refrain familiar to all parents.

His mother Erin*, however, isn't complaining. She's relishing every moment. Because until last November, Erin hadn't seen her son for six years.

He was taken from her aged nine by the family court, along with his then 12-year-old sister, and she was barred from any form of contact on pain of arrest.

She wasn't even allowed to send birthday or Christmas cards.

But Erin is no criminal, drug addict or child abuser. In fact, before her ex-husband took her to court amid their bitter divorce, there had been no complaints about her parenting whatsoever.

The children were removed and placed with their father on the 'expert' advice of one woman – the unregulated psychologist Melanie Gill – who'd advised a judge that the children had been suffering from 'parental alienation', a concept since discredited as 'harmful pseudoscience'.

The last time Erin saw her son, she'd driven him to a friend's house ahead of that day's court hearing, on December 18, 2019. 'He shouted, 'I'll see you later' and I didn't even get out and give him a hug or a kiss because he was already running down the path,' she recalls. 'I had no idea it would be the last time I would see him for six years.

'No one can explain how that feels. It's like bereavement – but nobody died.'

Erin was finally vindicated at a High Court hearing earlier this year when a damning judgment – revealed by the Bureau of Investigative Journalism – stated Gill never should have been appointed to the case.

It was the second time in seven months that Gill's evidence was thrown out amid what is becoming one of the biggest scandals to hit the family courts in recent years, wrecking untold lives. The Daily Mail first reported the story of Gill, 67, in October after Victims' Commissioner Claire Waxman demanded an urgent review of all the cases she'd been involved with. In January the former president of the family division overturned Gill's evidence in Erin's case. Sir Andrew McFarlane went on to make a new order that Dylan could return to his mother's care.

While the High Court did not criticise Gill personally, it did criticise her expertise in this area.

By then, however, Dylan had already taken matters into his own hands. Just before Christmas last year, the then 15-year-old packed a bag and left his father's home without so much as a goodbye – and went to find his mum.

Now, speaking exclusively to the Daily Mail, Dylan describes his family's devastation, caused by Gill's evidence against his mother – funded by his much wealthier father – and his enduring fury at a system he will never trust again.

'The environment at my Dad's was horrible and stressful and I'd had enough,' he explains. 'So, one morning, I sneaked out.'

While Dylan no longer had his mother's address, he was able to get it from one of her friends who gave him a lift there. Erin was working from home that day when she got an incredible call. 'It was a video call from a friend saying, 'I'm with [Dylan]' and she handed him the phone,' she remembers. There on the screen, through a blur of tears, she saw a young man – with stubble and broad shoulders – but with the same eyes as her little boy. 'I couldn't believe how deep his voice was,' Erin recalls. 'He said, 'Hi Mum, I'm coming home. We are 30 minutes away'.'

The initial reunion was short-lived, however, after eight armed police arrived at the door – alerted by his father after Dylan sent him a message saying where he was. Erin knew it was pointless to resist but Dylan refused to go back to his dad, meaning he had to be placed in emergency foster care. He finally, legally, moved back with his mother in January. 'I still have to hold myself back from hugging him all the time,' she says.

Erin, a well-spoken 43-year-old who is close to completing a law degree, is still getting used to living with a teenager.

'It's like when you first have a newborn and you are trying to work it all out,' she explains. Dylan, showing maturity beyond his years, agrees: 'She's figuring out how to be a mum again and I'm figuring out how to be a son. She has to parent a 16-year-old she's only known for a few months. I'm a completely different person mentally and physically.'

In his newly-painted bedroom, Dylan's old toys are proudly displayed among the usual teenage paraphernalia. Erin had kept everything: his Lego, Transformers figures and his favourite childhood blanket. Neither of them can let go of this time capsule.

'When the children were taken they weren't allowed to retrieve any of their belongings, not even their favourite teddy,' says Erin. 'I was told it would 'emotionally destabilise' them.'

It's hard to imagine a more painful and traumatic experience for a mother and child. Yet so much of this deeply disturbing case remains perplexing: how could this have happened?

Dylan has few memories of his parents being together; they separated when he was four. Erin met her ex-husband – a 'highly ambitious' City worker – in 2006 when she was 22 and he was in his 30s.

'He persuaded me to quit my job in the public sector and move in with him. Before I knew it, his parents were throwing an engagement party. Things were snowballing.'

Then she fell pregnant. 'I was in a state of panic. He was over the moon and railroaded me into a wedding before I started to show. I was young with no job or savings – it seemed like the best option.'

She claims the abuse started when she was still pregnant: 'He would push and pinch me and drag me by the arms. One night he locked me in a walk-in wardrobe. Afterwards there would be calm periods where he would buy me clothes and handbags and take me on spa weekends.'

Erin says she now recognises the behaviour for what it was but back then 'nobody knew what coercive control meant'.

After Dylan's birth in 2010 she tried to leave. 'That's when he hit me properly for the first time,' she alleges. 'I was breastfeeding the baby and he took him from me before punching me twice in the face and trying to strangle me.'

When a neighbour alerted the police, Erin claims her ex started crying and told officers she had tried to kill herself. They were both arrested and gave different accounts of the incident, before being released without charge.

Police records seen by the Daily Mail state that Erin had visible bruising to her face and neck consistent with her allegations. But fearful of losing her home if her husband was convicted, she withdrew her statement. A 'prolonged and sustained attack' on Boxing Day 2014, that required medical care, was the final straw, she claims. 'My daughter witnessed it – that was the tipping point.'

She filed for divorce and he moved out. Erin's ex has consistently denied ever being abusive towards her or the children and there are no convictions or court findings against him.

For the next four years the children lived with their mother and had regular visits with their father, with whom they seemed to get on well. 'He travelled a lot and wouldn't always take up contact but I never stopped him from seeing them,' she insists.

It wasn't until 2018 that she disclosed the full history of the alleged abuse to police. In July that year she received a letter informing her that her ex was filing for full custody of the children because of 'parental alienation'. Erin was aghast.

The police advised her, however, that addressing her allegations through the family courts, rather than going down the criminal route, would be quicker and she'd also be able to secure a protection order against him. 'In my stunning naivety I believed them,' she says. 'It's hard to imagine how it could have gone any worse.' Erin's ex continued to deny her allegations. Hiring expensive lawyers – while Erin mainly represented herself – he claimed she had neglected the children and turned them against him. He made allegations from 'the banal to the absurd', says Erin.

'He said I would leave the children to go to sex parties, that I was an alcoholic and a sex worker. None of it was true.'

Erin was convinced justice and common sense would prevail: then in April 2019, Melanie Gill was brought in by the Children and Family Court Advisory and Support Service (Cafcass), tasked with representing the children.

Gill is among a number of psychologists (including those who are regulated) who advise family judges on 'parental alienation' – the idea one parent has manipulated their child or children to reject the other. It's a concept that has gained traction over the years and spawned a lucrative industry, including costly treatments such as 'reunification therapy' where children are 'reprogrammed' to accept the rejected parent.

Gill describes herself as a 'highly specialised expert witness' and claims to have given evidence in up to 200 cases. She rejects mainstream clinical psychology, instead undertaking detailed interviews to examine 'unconscious processes'.

In reality, her qualifications extend to a third-class degree in psychology, plus a postgraduate qualification in Child Forensics, Psychology and Law – a diploma rather than a Master's Degree owing to the fact that she failed to complete her dissertation.

Her work is unregulated: she is not registered with the Health and Care Professions Council (HCPC) – and her CV shows no record of paid employment as a psychologist in a clinical setting.

She was paid well, however, to assess Erin's family. She received £16,000 before filing a 100-page report described by Erin's barrister as 'impossible to understand'.

Dylan was eight – and still living with his mum – when he met Gill.

He recalls being pulled out of lessons to speak to an endless string of professionals – and having recording devices and camcorders shoved 'right in my face'.

'I became used to one-sided questions but nobody was as blunt as Gill in trying to get me to bad-mouth my Mum,' he recalls. 'I remember being shocked at how direct she was. She would ask if Mum ever physically abused my dad but there were no questions about his behaviour.'

He remembers she once asked what scared him. 'I said foxes because one had recently attacked my cat. She then said, 'Are you sure you aren't scared of Mummy? Are you scared when Mummy drinks?' But nobody ever asked me how I felt when my dad drank half a bottle of whisky in one night.' Now Dylan realises it was about 'building a case against Mum'.

As Erin recalls: 'The report came in and all hell broke loose.' Without hearing from any other witnesses, District Judge Smith adopted Gill's conclusions as the court's findings – a decision for which he would later be heavily criticised by the High Court. He declined to examine the parents' allegations of abuse against each other.

Smith said there was no need for a 'factfinding' exercise, because Gill advised him that – even if Erin's allegations were proved – she would not change her recommendations. Complaints from both children about their father (which he denies) were also overlooked, including a serious allegation of physical abuse by Erin's daughter. On Gill's advice, Smith ordered the removal of the children to their father.

Erin was to have no contact with them whatsoever until she had undergone costly private specialist therapy (with a professional of Gill's choosing) which she was unable to access.

The day he was taken, Dylan remembers being shocked and confused when his father – instead of his mother – arrived to collect him from a friend's house, accompanied by a Cafcass officer.

Afterwards, says Erin, the mother of Dylan's friend described watching him being taken away as the most traumatising thing she'd ever seen. 'She said the Cafcass officer literally manhandled him out as he was grabbing on to the door frames and furniture, trying to resist.'

Dylan remembers being told that his mum was 'mentally ill' and 'crazy' and that he'd be staying with Dad from now on. 'I got really angry, shouting at her to get out.'

Erin hit wall after wall trying to challenge the order – the children's Christmas presents remained unopened. Dylan 'shut down' and retreated into his online gaming world.

A year later his father moved the family nearly three hours' drive away. 'We changed schools which was hard but it was also a chance to create a new persona,' says Dylan. 'I started telling people my mum was dead. It was easier.'

His father worked long hours, he says, and although he never hurt him physically, Dylan claims he would drink heavily, get angry, shout and break glasses.

A psychotherapist – an associate of Gill's – was arranged for the children (costing £200 an hour and paid for by their father). The advice given was also on the basis of parental alienation and that the children's mother was a risk.

Dylan refused to cooperate. 'I'd just sit there in silence,' he says. His sister – of whom both Dylan and Erin are fiercely protective –went through six years of this therapy, however. She's 18 now and getting on with her own life.

'I think it will take her a long time to come to terms with the reunification programming she was subjected to and the impact it has had on her. I hope that in the future we'll be close again,' says Erin.

Gill did not respond to our approach for comment but has told the The Bureau of Investigative Journalism that she is well qualified to perform the role of expert witness and has years of specialist training. She claims to be the victim of a 'witch hunt'.

In a 2023 case, she told the court: 'I have been challenged and questioned on my qualifications in every single private law case I have ever undertaken and I have never been criticised.' While Gill's days of advising family judges are over, the damage caused to this family cannot be reversed.

Erin says: 'Gill has caused such psychological trauma and she needs to be held accountable for what she has done.' As for Dylan, he says: 'Before, I enjoyed spending time with Dad. But after he took me away from Mum I don't have an ounce of love for him. I never want to see him again.'

*Erin and Dylan are pseudonyms