I found this kindof shocking to be honest.. only because I never.. and I think most the people are the world didn't pick up on it as well.. Ah well.. good on her for doing that, she wasn't looking for any more attension for her books, she was answer a kids question - honestly, not being afraid of the truth - or who he was. Good on the women!
JK knew the series would end after the seventh book, so maybe earlier it popped into her head, and she decided to withhold that information until the end of the series as she/her publicist might have been worried of such news being spread halfway through the series
It's a smart move, as I can guarantee that if she had stated this earlier, there would have been major issues, and possibly a slump in sales as many parents already didn't want their kids reading about witchraft, and now the wizard is gay
Not to seem ignorant, but earlier (as you all know) being gay was much more taboo than it is today
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