When we went- hubby wore a regular suit and tie at formal night (and shirt/tie or polo at casual nights)
The kids were 15/12/4 at the time witht he youngest a girl. The boys wore polos and dockers most nights and a dress shirt/tie/coat for the oldest and dress shirt/tie for the middle one. My littlest girl wore Easter sunday type dresses every night.
I just wore a black cocktail dress. I packed it in a regular suitcase the day we left home and unacked it when they delivered our luggage (before we found our stateroom) and threw in some jewelry and we were off. I actually didn't even otice what anyone else was wearing..the tables on the fantasy were kindof in little sections.
Carnival Fantasy 6/05
RCCL Sovereign of the Seas 4/07
RCCL Navigator 12/07
RCCL Navigator 11/08
RCCL Liberty 7/4/09