In his will, my father had requested 3 years of qadha prayers be performed on his behalf. My elder brother whose responsibility was to execute the will performed 3 years of qadha prayers, but I think my late father’s qadha prayers were more than 3 years. Are we just obligated to perform only 3 years of qadha prayer according to the will or we have to perform more if we consider it probable that our late father had more qadha prayers?