Is it permissible to pay Zakat on behalf of a father who refuses to pay it?

Zakat is one of the pillars of Islam; it is not permissible to withhold it once it becomes due. Individuals can do nothing towards someone who refrains from paying it except to enjoin what is right and forbid what is wrong, warning them of the danger of withholding Zakat. If they persist, then Allah is their Reckoner. It is not sufficient to pay it on their behalf without their permission, because the intention for Zakat is a condition for its validity.