***This phase of a child pretending to be the opposite sex will vanish very quickly,***
Back in the olden days it was common for a mom to dress her baby boy as a girl for several years. When the boy got his first pair of long pants was a day of celebration.
She didn’t “dress him as a girl”. It was standard procedure because it was much easier to access that dirty area when those kids didn’t know how to hold it and use potty. Simple practicality.
As far as what is male/female, lots of cultures have different ways. We all know about kilts, Roman togas (and VARIOUS cultures did/do that - “skirts” for men), etc. Also in old Siam apparently women wore “pants” while men wore “skirts”. Made sense in a way - to protect women from easy access (there that is again).
Sorry for the diversion. Does get one to thinking.