Mu mother in law has epilepsy and it has gone now for 2 days what can I do so she can get her memeory back?

Not sure of question. Has the siezure activity continued two days? Has it cleared but memory for things hasn't come back for four days? If she is still having seizures that is an emergency & she needs help immediately. If her memory hasn't returned, memory for just before and after a seizure is often not recovered at all. On medication she may be sedated enough that her memory is faulty. Call her doctor for help asap.
Epilepsy in mother. I am not sure how old your mother is, the kind of epilepsy she has, the frequency of epilepsy, the medications she is taking, etc as all these factors can contribute to memory impairment. However there is a condition called epilepsy ammesic syndrome with adult onset described by dr gallassi in bologna italy. This kind of epilepsy responds favorably to certain antiepileptic drugs.