Just my two cents: we have cruised many times with our daughter - 6 alone on Disney. Disney cruises are very $$$$ I would wait til your youngest can do the kids clubs - everyone will enjoy the trip much more and you will receive full value for your money. They don't have to spend every waking moment in the club - vacations are for family time - but that way it is an option and if they are anything like our daughter - they will LOVE them.