She should fast it and a day earlier or after it! If she is unable to do 
so, she should feed a poor person for every missed Friday.

My mom (age 65 plus & chronic stomach patient) a long time ago wowed (nadher) to fast every Friday for something (not knowing that fasting on Friday is disliked), please advise what; 1. To do for the missed nadher fasts 2. If she is unable to fast due to health issues 3. If her health allows her, should she fast on Friday or some other day in the week to fulfil nadher.

Fasting | October 24, 2015 5:38 am
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I have heard from one of ur class that we can combine intentions eg:-fasting on the day of Arafat with the intention of making up missed Ramadan fasts n inshahAllah getting the rewards of both..but y is this not applicable with the 6days of fasting on Shawwal.??
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I was fasting on 9th Ashura and when I woke up I felt sexual temptations but I tried not to think about it and I made thikr. Shortly after to my suprise, without doing anything at all, maniy came out. Is there any sin upon me, and is my fast OK?