Can the husband have intercourse with his wife while she is under a nursing contract?

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If the nursing infant is asleep or engaged in something else, the husband has the right to conjugal relations. This position is held by Al-Shafi'i. The basis for this ruling is that the husband's right to intercourse is established by the marriage contract and cannot be voided by a doubtful claim (i.e., the potential harm to the milk). Furthermore, intercourse is permissible with the guardian's consent, and thus it is permissible without it, as the guardian has no authority to consent to something that harms the child or nullifies his rights.