Mine is the 17th, and we'll be embarking for a 4 night cruise, that day.  
Since people like to get dressed up with goofy shirts or accessories for cruises, would it be crazy to wear some sort of "birthday apparel" that day? 
(T-shirt/sash/crown)?
https://www.amazon.com/gp/product/B01IPMSL5U?th=1&psc=1https://www.amazon.com/Forum-Novelties-Happy-Birthday-Glitter/dp/B00AIF9C92/ref=sr_1_9?ie=UTF8&qid=1496942174&sr=8-9&keywords=birthday+crown+adult