Teach my kid that respect goes far. If that's how a person wants to be addressed, address them as such.
When I was five my aunt owned a makeup store in downtown Toronto. My dad and me were around the shop and popped in for a visit. While there a person said hello to me, and it was a trans person. Scared the shyt out of me and I ran out of the shop screaming. My dad came and got me, bent down to look into my face, and told me that people might be different but they always deserve respect. This was coming from a 25 year old black man. I watched him apologize to the person. It stuck with me for life. A simple 2 minute interaction and what my father taught me.