The brother-sister syndrome is of paramount importance in Arab cultures and plays dominant roles in social structure and elite as well as oral folk literatures, and the core of this dyadic relationship is a stable pattern of sentiments involving the entire family. It may be summed up as follows: brother-sister mutual love, sister-sister rivalry, brother-brother rivalry, child-parent hostility, husband-wife hostility, brother-sister's husband hostility, sister-brother's wife rivalry, brother-sister's child affection, and brother-brother's son hostility. Here, El-Shamy examines sibling relations as expressed in the narratives contained in a modern popular edition of the Arabic collection Alf laylah wa-laylah, commonly known in English as The Thousand and One Nights.