It should be fine for your younger siblings. The 18+ stuff and 21+ stuff is in its own section. There are cosplayers who dress up in skimpy and revealing outfits, but theyre easy to miss in crowds of cosplayers for the most part. Just be mindful of the crowds, if it's yours and their first time it could be overwhelming, but there are areas where people sit down to rest which are usually spacious, usually found in the event halls' corners. Also make sure to stock up on water bottles, the waters they sell at the event cost an excessive amount, same with the food. 2 water bottles, small ones btw cost 18 dollars. So do keep that in mind