Pitch for my dragon lore: when they first hatch, young dragons look a lot like their parents. But as they find themselves, form their own identities, their appearance changes in reflection of that, sometimes quite drastically indeed. Scale colors, horn shapes, even body type and myriad other features.
This is essentially another expression of the same principle that causes dragons born in human shape to tf when they realize what they are. The dragons I usually write are creatures whose external form reflects their inner selves.
Which ... you know, that seems kinda funny, thinking about it. I'm extremely heart on my sleeve. I'm infamously predictable and struggle to hide myself away or keep secrets, especially from those close to me. In a way, the way I write dragons reflects who I am.