Ignore that it's the wrong time of year.
17yo dd needs a prom dress. Most people will be wearing the fashion which is an unlined satin nightie-slip thing. I've attached a pic as an example.
Dd is not keen on those. What else is fashionable?
(She hasn't asked me to ask btw, I'm just procrastinating when I should be working because prom dresses are more interesting than curriculum reform).