A guest at a dinner party hosted by my sister, who throws parties with her best dishes and crystal, announced to everyone that she had brought a dish that she was not intending to serve. The guest had been telling people how rude my sister was not to serve the food she brought, causing anger at her mother. This has led to an angry exchange of words between the two parties. Despite this, Miss Manners believes an apology is due even if the guest is innocent.