Where should the child of a Muslim woman who married a non-Muslim be buried?

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The preference is for the child to be buried separately, not in the Muslim cemetery because the mother is a disbeliever and would cause the child distress from the punishment there, nor in the disbelievers' cemetery because the child is Muslim and would suffer from their punishment. This opinion is attributed to Ahmad and narrated from Wathilah ibn al-Asqa'. Regarding the burial orientation, the back of the mother is placed toward the Qibla on her left side, so that the face of the fetus is toward the Qibla on her right side, as the fetus's face is directed toward her back.