Thoughts on fabric ideas

Hi It's been a while. My 14 year old daughter is weeks away from her first dressy event. She and her cohort of boarders will be going on a dinner cruise in about three weeks. It will be her first sort of "dance party" type event and she needs a dress. The dress code is "cocktail" style but it's been specified that it has to be pretty but not too fancy. These are unknown waters for me! And I think I need a little help. She likes the fit and flare style of dress so I have been searching through my current pattern collection for something that might be suitable. She wants pink - because naturally it is her favourite colour and because I have to buy shoes made to order we have to decide on these things early. Is silk too fancy do you think? Or should I go for a different fabric? And what kinds should I go for? I can do a sort of muslin for fitting purposes while she is still away as I took her measurements but when she is home over the long weekend (first weekend in March) I will need to make it hollis bollis so she can return to school with it. So, can you assist please? Thanks in advance Tamara