There’s plenty of pictures of me as a kid dressed up as a girl. And having a preference for things “soft” and “pretty” and preferring mom to dad and wanting sisters and not brothers.
I’m still a fairly well-adjusted cishet dude. Because these traits in kids aren’t necessarily signs of actual transgender identity (any more than cross-dressing is). Family stories about how I insisted I was a girl and grew my hair long early in life are often told to prospective dates (and entirely in keeping with my rather stubborn childhood tendencies in general).
Gender identity isn’t a state locked in from birth, it’s something we come to understand as we negotiate the confluence of our biology, our society, and our mental self-image. It can’t help but be bound up in our understanding of what it means to be of a certain gender in the world. Because of that, claims of being one gender or another should largely be treated as provisional until later in life (as in, probably post-pubescence).
Yeah, I’m not disagreeing, I’m just pointing out that an 8 year old’s personal gender choice isn’t necessarily final. It may be. It also may not be. Treating it as an absolute part of their identity would be a mistake in any case. Accepting whatever that choice is and encouraging them to explore what that’s like is good in any case.