Dear Queenie,
My sister’s children do not call me “Aunt”, they just call me by my name the same as their parents.
Queenie, I find this very rude. What do you think?—Offended aunt
Dear Offended aunt,
You should talk to your sister about this. Childen repeat what they hear their parents say, and it is up to the parents to explain to them what they should call you and how they should address you, and to enforce the rule.