Prince Harry’s mental health charity, Heads Together, has invited a U.K.-based transgender youth charity to join its wellness efforts, according to The Telegraph.

The charity, Mermaids, participated in a roundtable this month at a YMCA outside of London that was organized by the Royal Foundation, Prince William and Prince Harry's umbrella charity. A Royal Foundation spokesperson told the newspaper that Heads Together meets with groups like Mermaids "to best understand the issues young people are dealing with today, and gain a clear understanding of what support is being made available."

Mermaids tweeted its thanks Tuesday to the Duke of Sussex “for his unwavering support of young people and promotion of positive mental health and well-being.”

Thanks to @heads_together for organising such an amazing event and to Prince Harry @KensingtonRoyal for his unwavering support of young people and promotion of positive mental health and well-being.https://t.co/XAd4qJ4cVu — Mermaids 🧜🏻‍♀️ (@Mermaids_Gender) April 23, 2019

The transgender charity's participation in the meeting is noteworthy considering the vocal criticism that has been directed toward the organization — and transgender advocates more broadly — by the public and the media in the U.K.

In 2017, Prime Minister Theresa May promised to reform the 2004 Gender Recognition Act and "streamline and de-medicalize the process for changing gender, because being trans is not an illness and it shouldn't be treated as such." That led to a contentious public comment period; the full report is expected to be released this year.

According to a June 2018 YouGov poll of U.K. voters commissioned by Pink News, just 18 percent of British voters support allowing transgender people to "self-identify" when changing gender on legal documents instead of waiting for the approval of a medical panel.

"While the U.K. has made significant progress in expanding and protecting the rights of transgender people, they are currently engaged in a fierce debate about improving policies for transgender people to have their gender identities affirmed on government documents," said Sarah McBride, a transgender activist and national press secretary at Human Rights Campaign.

McBride said a "small, but vocal" group of anti-trans activists have targeted Mermaids for their work.

"To have Prince Harry so publicly and clearly embrace the lifesaving work of Mermaids sends a powerful message to trans youth across the United Kingdom and the Commonwealth that they are seen and valued," she added.

This princely support for the LGBTQ community is not new. Mermaids CEO Susie Green told Pink News that Harry called the charity's work “amazing” at a 2017 event at Buckingham Palace. That same year, Prince William, the Duke of Cambridge and second in line to the throne, won the Straight Ally award from the British LGBT Awards.

In January, Prince Harry’s wife, Meghan Markle, the Duchess of Sussex, who is pregnant with their first child, reportedly told friends that she plans to raise their child with a “fluid” approach to gender, including a gender-neutral nursery, according to Vanity Fair.

Twitter users saw echoes of Harry's mother in his outreach to the LGBTQ community. Diana, the Princess of Wales, worked to destigmatize the lesbian and gay community in the United Kingdom. During the HIV/AIDS crisis in 1987, Diana opened the U.K.’s first AIDS ward at Middlesex Hospital and made a point of being seen not wearing gloves while shaking hands with AIDS patients.

“She did this to explode the myth” that AIDS could be spread via touch, a palace spokesperson told United Press International in 1987.

I agree, just like his mum, when HIV/AIDS charities were seen in the same way ´Controversail´ and used as politically motivated hate by the media. On the right side of History Harry! — Samantha Hamer🧜🧚🐙 (@ParaMojoOrg) April 23, 2019

A spokesman for the Royal Foundation told the Telegraph that Mermaids is one of a number of organizations "working on the frontline to support the mental health and well-being of young people in Britain."

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