My wife vomited during Ramadhan. She thought that her fasting is invalid for that day and she has to repeat it, she drank milk after that. She does not know that this is a violation of the fast. Now should she repeat the day fast or repeat with Kafara?
Praise be to Allah, the Lord of the World; and blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
Your wife should make up for this day but there is no expiation on her as she drank believing that her fasting was nullified and this is a mistake. Ibn Abbas narrated Prophet said: "(Almighty Allah forgives my Ummah's mistakes, forgetfulness, and the acts on which they are forced)".
Know also that vomiting is of two kinds. The vomiting that is deliberately caused by the person; this nullifies the fast. The vomiting that is involuntary does not nullify the fasting. The Prophet said: "If vomiting forces its way out, you are not asked to pay that day. But if one of you deliberately vomits he should make up for that day". [Ibn Majah]
Allah knows best.
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