Clothes Don’t Make The Man
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“This is a very common behavior, and again, it’s a step in kids’ figuring out gender identities: Before about age 4, children may be able to identify a picture of a person as either male or female,” the pediatrician explained.
“But they may think that if the subject changes clothing or hairstyle, he or she changes sex as well. Dress-up helps kids test out theories and arrive at a more mature understanding that clothes don’t make the man (or woman).”