This is permissible.

I have pending ramadaan fasts. So before completing those fasts if I keep other nawafil fasts for eg 9th and 10th of muhharram then will these nawafil fasts be considered as they are or they will be counted into my pending ramadaan fasts?

Fasting | March 30, 2014 1:04 pm
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I am keeping my qada fasting of ramadan.yesterday night i made niyyah but i did not wake up for suhur.as i made niyaa so i contin ue fasting wihout suhur.is this fasting is valid?( generally i do suhur with a glass of water and date, i dnt eat heavy food.
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If a sister is used to fast every Mondays and Thursdays and her husband agreed on that and she should not ask him every time she fasts,but its happened that in a morning he approach her and they have intercourse.Will Allah count a daily fast for her as she was used to do this (ie.fasting)and she only obey her husband without telling him that it is a fasting day.