Is it permissible to supplicate for seeing a deceased father in a dream?

A Muslim is permitted to supplicate for any good, both in this world and the hereafter, without transgression or asking for what is impossible. There is no harm in asking Allah to see the deceased in a dream, because it is permissible, possible, and common, and there is no legal prohibition against it. It is better to focus on asking for forgiveness for the deceased and seeing them in a good state. The principle of wishing for a vision and asking Allah for it is permissible, and it has been narrated that Ibn Umar supplicated for that.