Traveling with our 18 year old - first week of Jan. for a 10 day cruise to the Panama Canal, Aruba, etc. We hope to be on the Brilliance Holland America and Celebrity were fabulous but we want to try something to appeal to our 18 year old. On average, during early Jan, are there many 18-20ish people on board? Now I'm reading that most cruises above 10 days may not appeal to the younger crowd. We have cruised to many places, but that is when our child was younger. At 18, we are hoping she will meet some non-rowdy, friends.