It was a case that tore a family apart – and exposed the faultlines in an increasingly bitter global row over the rights of a child to define their own gender.
The battle late last year in Texas between two parents over the gender identity of their child sparked a raft of bills across the United States that have been dubbed anti-LGBT by campaigners and pro-family by conservative groups.
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A global rise in the number of teenagers seeking to go through gender reassignment has also spurred a series of court cases around the world around the age at which young people are able to choose to transition – and who has the final word.
The escalating debate has revealed a gap in global laws, pitting family and religious groups against trans activists for legal rulings on whether the decision to transition is up to the child, parents or doctor.
For Currey Cook, counsel at LGBT+ rights group Lambda Legal, conservative groups have focused on trans minors as "an easy target for people who are anti-LGBTQ in general".
"This is just the next target," Cook told the Thomson Reuters Foundation.
Yet others, including Susan Evans, a former employee at Britain's leading gender identity clinic, the Tavistock and Portman NHS Foundation Trust, argue that children are being put at risk.
Puberty blockers, which delay the onset of puberty and are usually the first step in the process of transitioning, are nothing more than "experimental drugs", said Evans.
As part of the next stage, hormones - such as testosterone and estrogen - will be prescribed when the child, in most countries, reaches 16 or 18.
Gender reassignment surgery is widely restricted to adults over the age of 18.
Under some of the proposed new laws across the United States, doctors could be barred from prescribing puberty-blocking drugs to children,
A measure introduced in South Carolina last year would revoke the licenses of doctors who treat trans children.
Meanwhile the South Dakota legislature voted down a bill that would see doctors charged with a misdemeanor if they prescribe puberty blockers. "The world is upside-down that protecting children from sterilizaiton (sic) and mutilation is causing a firestorm," Republican state representative Fred Deutsch, who sponsored the bill, said on Twitter ahead of the vote on Feb. 10.
Deutsch's office was contacted for comment but with no response at the time of publication.
The issue has spilled beyond the borders of the United States, with many countries either mulling new laws or moving to update them.
"Access to transition-related healthcare for minors is a hot button issue for Europe and around the world right now," said Cianan Russell, senior policy officer at LGBT+ rights group ILGA-Europe.
Last month, Brazil lowered the age at which young people can access gender reassignment surgery from 21 to 18 and dropped the age requirement for hormone therapy from 18 to 16 - although those under 18 must have the consent of a parent or guardian.
Mexico is examining the laws governing young people looking to transition.
Last year, the Mexican authorities said all LGBT+ people, including those who are trans, should be able to access medical care free from discrimination with children given access to puberty blockers.
Australia's proposed Religious Discrimination Bill would give medical professionals the right to refuse treatment on religious grounds, according to Nikita White, activism support coordinator at Amnesty International Australia.
And in Canada, a court ruled against a father last month who had sought to stop his 15-year-old undergoing treatment to become male.
Britain has seen a similar flurry of legal activity.
Last month, Evans applied to Britain's High Court for a judicial review of the age at which children can be prescribed puberty-delaying drugs, currently available to those under 18.
Evans, who spent 11 years at the Tavistock and Portman NHS Foundation Trust as a psychiatric nurse and senior clinical lecturer, said the long-term effects of puberty-blocking drugs were as yet unknown.
However Stephen Whittle, professor of equalities law at Britain's Manchester Metropolitan University, said the current domestic laws governing medical healthcare for young trans people were fit for purpose.
"There's absolutely nothing wrong with the current legal system, which requires doctors to obtain informed consent before providing any treatment of any sort," Whittle said.
Part of the issue is that current laws have yet to catch up with the rapidly evolving nature of society, particularly in terms of trans people's rights, added Jonathan Cooper, a barrister at Doughty Street Chambers, a leading human rights practice.
Referring to the current situation in Britain, Cooper cited the UN Convention on the Rights of the Child (CRC) and stressed that the CRC guarantees children the right to autonomy and physical, mental and emotional integrity.
The CRC also recognises the rights of trans children, Cooper added.
He warned that preventing trans youth from accessing puberty-delaying drugs and forcing them to go through "the hell of puberty" could be deemed "inhuman and degrading treatment", under both the CRC and Britain's Human Rights Act.
Legal gender change
The rights and protections for trans people of any age remain relatively new – or non-existent – in many parts of the world.
Europe is seen as the standard bearer, with the most liberal laws governing access to puberty blockers or gender assignment surgery.
According to a report from the European Commission, "EU primary legislation contains no explicit references to gender identity, gender expression or sex characteristics" – unlike sexual orientation, which is protected under EU law.
But the EU's equality directives do apply to discrimination arising from gender reassignment, the report noted.
Malta – often seen as Europe's leader in terms of LGBT+ rights – stands alongside Ireland and the Netherlands in allowing access to hormone therapy at the age of 16.
Parts of the Americas pursue a similar approach to Europe.
In Canada, medical regulations state puberty blockers may be used for girls as young as 10-and-a-half and boys aged 11-and-a-half. Hormones may be administered to teenagers from the age 16.
Further south, Uruguay in 2018 became one of the world's most progressive countries in terms of rights for trans children when it approved a law allowing anyone under 18 to receive medical treatment paid by the state.
Yet despite the advances for trans rights in parts of the world, the welter of legal challenges underway reveals the urgent need for change, said Jessica Stern, executive director of LGBT+ rights organisation OutRight Action International.
"The law has not changed as rapidly as society has," she said.
"By definition the law will always lag behind cultural attitudes, but this is an area where the law is not just lagging behind but running fast in the opposite direction away from the pace of social change."