What ungrateful snobbishness, to be invited to a family celebration and expect your hosts to shell out £200-plus for each case of champagne. There are plenty of 'traditional method' sparkling wines which are a good substitute, easier on the pocket - and who the hell notices after six glasses, anyway? You can try to pass them off as 'champagne' but my tip is to be honest and, if asked, declare what you're serving from the start.