What is the Shar'i (Islamic legal) position regarding the eldest brother demanding that his siblings pay for their mother's treatment costs, which he covered from his own money? Are these costs considered a contribution to the father's inheritance, or should they be repaid to him at their current value, especially since there is an inheritance from the mother that covers the treatment costs?

Expenses incurred by the son for his mother's treatment:

1. If the mother is in financial hardship and the son is wealthy: He is obligated to provide for her. If she has wealthy siblings, the madhhabs differ on how the expenses should be distributed among them.

2. If the mother is wealthy and the son spent as a volunteer: He is not allowed to revoke his donation.

3. If the mother is wealthy and the son spent with the intention of being reimbursed: He has the right to claim what he spent, and he must take an oath if the heirs do not believe him.

After the death of the wealthy mother, what the son spent is considered a debt on her estate, to be repaid before distribution. The heirs are not obligated to pay it if she left no wealth.

The brother's claim for his debt is against the estate, and the heirs are not obligated to seek its fulfillment unless a claim is made.

What the brother paid is a debt on the estate, and he can reclaim it from the heirs if the estate has been distributed. This money is not considered a contribution to building the father's house, because the capital of a company must be a present asset, not a debt.