Your kids wouldn't have freaked out at your nakedness when they were little floo, they'd have thought nothing of it. They must have seen you when they were babies and toddlers. That's normal and natural within families and the little ones grow up knowing what an adult looks like, they don't even think about it.
What I think is wrong is putting pictures on the internet of yourself and child naked because everyone, not just close family, can see it and the child had no say in the matter. I consider it rather exhibitionist but, OK, if someone wants to expose themselves they can, but not expose their child.
(I laughed at the story of the girl wanting to keep her pyjama bottoms on whilst giving birth. I've never heard of anyone giving birth completely naked, they usually have a short, loose nightie on or hospital gown. Even in a birthing pool.)