A mother posted asking for advice on the legaladviceUK reddit after receiving this letter.
i.imgur.com/Oj9iT91.png
This is her explanation. It involves Mermaids training the school.
archive.is/6KY7X
She didn't get good advice because that subreddit is moderated by TRAs. The TRA mods tried to find evidence the letter was fake and they wound up deciding that it had not been photoshopped. Then, after calling Mermaids for advice on the situation, they locked and deleted the thread to stop the story spreading.
archive.is/d5nFU
I hope I'm doing the right thing by posting this. I'd hate for the mother and child in this case to get hunted down by the media. But I hope they can access some help.
Just to note that I do not know who they are, I just saw the posts. And although the letter doesn't seem to have been photoshopped, there is nothing stopping anyone from printing out a fake letter and scanning it. But it looks legitimate.