Wrong. Kids' intellects and ability to draw conclusions may not be as developed, but their perceptions of what they see are probably more accurate than adults'. So she does need to help this child form an appropriate attitude. And it wouldn't hurt to "help" the principal and the school board, either. Oh, and start homeschooling.
There were many reasons we homeschooled, but one came from my very first parent teacher conference with our oldest child’s kindergarten teacher. He was a pretty nerdy quiet kid(kind of miss that stage!!) so I wasn’t anticipating any problems. I was wrong-she was very upset about one thing and made it quite clear that we needed to address it. He quoted the bible as it relates to morality. This was an older church going woman, but said it absolutely must not happen again. Ever.
Kindergarten kids are observant and quite literal so will comment on situations that don’t match their worldview. With transgenderism their innocent comments could bring reeducation to the whole family.