I found sources.
The word “man” was gender neutral and referred to both sexes until the 13th century
The female specific pronoun “she” was invented in the 12th century.
The word “girl” was gender neutral and referred to children of both sexes until the 15th century
High heels were invented for men and were worn predominantly by men until the 16th century
From the mid 16th century to the 19th century boys would typically wear dresses until the age of 7
Until the early 1930s pink was considered the appropriate colour for baby boys and blue was the colour for baby girls
In 2017, a Christian couple pull their 6yo son out of a primary school because his classmate is transgender – citing their “traditional beliefs” IMPORTANT NOTE: Last source is transphobic and from a pro-life website that attempts to defend the dumb ass couple. Feel free to ignore it if you prefer, but it was included for the sake of accuracy.
Reblogging because verifiable sources make every information 70% better. Thanks for the addition!