No need to spend that much especially on CCL which I wouldn't go on b/c it is too risky. I have heard too many bad stories to take a chance. We just booked (2 adults and 2 kids) a cruise on the Caribbeam Princess mini suite (324 sq. ft.) plu balcony for 3400. WEven with the flights we are well under 10,000. We did a bunch of research and it seems that RCL and Princess are the best for families. Many kid programs. RCL was more expensive and the accomodations were smaller. You would probably need two rooms on RCL. Good luck!