What's a Nice Way to Put This?

[Calgacus]

I suppose a lot depends on your age. I don't know exactly how old you are, but if you are an adult I would show them this website, tell them that the kilt is not a costume, it is simply a mode of dress, then wear your kilt with pride.

If, however, you are not yet an adult my advice would be to do as your parents ask even if they are misguided or misinformed. It is no great hardship not to wear your kilt, and you are living under their roof after all, so you can expect to have to follow their rules. Besides, you will be an adult soon enough and can then make your own decisions about how you dress.

The way I see it, making compromises like that shows your parents respect, and a wise man does all he can to keep his parents happy. You never know when you might need them in the future.