What is the legal ruling regarding children's refusal to pay additional sums to their father after a court judgment, and their negligence in visiting him due to his imprecations against them?

If the amount given to the father suffices his essential needs, then it is not obligatory to give him anything extra. However, it is preferable to give more, as much as one is able, in accordance with the texts on honoring parents. Honoring parents is an emphasized obligation, and one must always be kind to them, even if they mistreat. The supplication of parents against their children without a just cause is not answered because it is a sin.