Find Your Cruise
Seabourne, SilverSeas, Azamara and there are 2 child free P&O ships. Saga are for over 55 only.
As well as the ships mentioned by Aldrich, Fred. Olsen re-position some of it's fleet in the caribbean for the winter months, these ships are by today's standards very small and more importanly, outside the school holidays have very few children onboard.