H.H.
Hi T.,
NO - It does not sound bossy. He is YOUR son - and YOU know what he would like best!!! I say, have a swimming trunks party, and everyone can wear swimming trunks!!! Ha, Ha!!! But I think that it is great when I am given a suggestion on what to get a child for a birthday party. Especially since all kids are different and like different things. I say, when it comes to your child, you are in charge, and you can do what you want!!! Hope this helps!!!