What should a young woman do if she has missed fasting days in Ramadan for several years and does not remember the exact number of days, and is it permissible for her to observe voluntary fasts before making up what she owes, and what is the ruling on her parents paying the expiation for fasting on her behalf and on behalf of her siblings?

The missed fasts of Ramadan must be made up. If the exact number of days is not known, caution should be exercised in determining the number until one is reasonably certain of having fulfilled the obligation. The obligation to make up the fasts does not lapse due to the passage of time or ignorance of the number of days. Furthermore, an expiation is due for delaying the make-up fasts until the next Ramadan without a valid excuse. A mother's payment of the expiation on behalf of her daughter is not valid unless it is with the daughter's permission or by her authorization.