Is Zakat due on a inherited sum from previous years that could only be withdrawn this year?

The money your father left in the Islamic bank became the property of the heirs after his death. Zakat is obligatory upon whoever's share reaches the nisab (minimum taxable amount), or whoever's nisab is reached by adding their other wealth to it, after a hawl (one lunar year) has passed since they came into possession of the nisab.

The inheritance is to be divided as follows: - The mother: One-sixth (1000 dinars). - The wife: One-eighth (750 dinars). - The remainder (4250 dinars) is to be divided among the sons and daughters, with the male receiving the share of two females. - Each daughter: Approximately 265 and one-third dinars. - Each son: Approximately 531 and one-third dinars.