Will be Proposing on Disney Dream

I will be proposing to my girlfriend on our cruise later this month. We will be on the Dream for the 5-Night Halloween on the High Seas Bahamian Cruise stopping at Castaway Cay, Nassau & Lighthouse Point. My brother, his wife, his mother in-law, and his son will be with us. We will also have our 3 year old daughter with us as well. I'm looking for any cool ideas. My first inclination is to have our daughter involved somehow but that's just a thought.