What is the ruling regarding someone who doubts whether she made up the missed fasts of the first four years after puberty and does not remember anything? Should she fast the days about which she is uncertain (36 days), or should she disregard this doubt?

Whoever doubts whether they have made up for their missed fasts, the basic principle is that they have not. It is obligatory to make up the number of days about which there is doubt, so that one's conscience may be cleared with certainty. It is not necessary to make up for a whole month, but only the number of days that were missed. If the doubt is due to whisperings (waswasa), then one should not pay attention to it.