Gender and sexuality are often already well-established long before puberty. Here is some content I created that includes details about how young children are when they begin to be able to identify these things about themselves and others: https://www.facebook.com/resil...1651875480?__tn__=-R
Here are some resources I used:
https://www.healthychildren.or...ion-In-Children.aspx
https://www.mayoclinic.org/hea...dentity/art-20266811
And some other resources for this topic with young children: https://www.genderjusticeinear...ldhood.com/resources