Thanks everyone - alot of food for thought. The only option open to us was to defer the cruise - which was considered but is not possible given personal circumstances, only other option was to lose 55% of the cost of the overall cruise (again not a very realistic option). Catch-22 comes to mind.
In regards to being next to crying babies - I appreciate the concerns of other passengers.
Our children are well mannered, quiet and very considerate. The baby, to date, has also been very placid. Our own holidays tend to be ruined by unruly children, rowdy/drunk teenagers, rowing adults, blaring radios and TVs, slamming doors - ie crying babies are near the bottom or our own 'nuisance' list.