Dear Ann Landers,
A social craze called Mixed Mates has hit town. The invitation we received yesterday read: "You are cordially invited for cocktails and dinner at Bill and Mary X's home on January 25. But you can't come with your husband. He must escort someone else's wife. You will not know the identity of your escort until he arrives. Your husband will soon receive a phone call assigning a date. But it must be kept a deep, dark secret. Of course you will be taken home by the man who brought you. R.S.V.P." I don't want to be a wet firecracker, but the whole idea offends me. My husband says it's novel and should be fun. What would we tell our teen-age children about such a party? Help, please.--Fraidy Cat

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