All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His slave and Messenger.
Fasting Ramadan is a pillar of Islam that should be observed with keenness. If a Muslim does not observe it out of ignorance or carelessness, then he must immediately repent and make up for the days that he has missed and feed a poor person for each day that he has delayed until the following Ramadan came. If a Muslim breaks a day of fasting in Ramadan by having sexual intercourse, then he must offer the major expiation, which is to free a slave, fast two consecutive months, or feed sixty poor people respectively. He has to abide by the order set by the sharia concerning these options so that if the first is not available or affordable he moves to the next. According to the preponderant scholarly view, this latter ruling is specific to men,.
However, if a Muslim breaks his fast in Ramadan because he is sick, then he is required to fast the days that he missed after getting well. Allaah says (what means): {… and whoever is ill or on a journey—then an equal number of other days…} [Quran 2: 185]
As for your current situation, you have to assess the condition of your mother. If she is expected to recover, then she should wait until Allaah grants her recovery and then make up for the days that she missed. If it is not expected that she will recover, then she is only required to feed a poor person for each day that she missed.
Allaah Knows best.