Is the prayer of parents against their children answered even after the disobedient child repents, or if the parents pray constantly with and without reason?

The general principle is that a mother's supplication against her disobedient child is answered. However, some scholars have qualified this by stating that it applies only if the child is an infidel or excessively disobedient, with no hope of their righteousness. Therefore, if the child repents from their disobedience, we do not expect the mother's supplication against them to be answered.

As for a mother supplicating against her child without cause, it is impermissible, considered an injustice and a sin, and will not be answered. This is based on the Prophet, peace and blessings be upon him, who said: "Do not supplicate against yourselves, do not supplicate against your children, and do not supplicate against your possessions, lest you coincide with an hour when Allah grants what is asked, and He answers you." Narrated by Muslim. And his saying: "The supplication of a servant continues to be answered as long as he does not supplicate for a sin or for the severance of ties of kinship." Narrated by Muslim.

The hadith "There are three supplications that are answered without doubt: the supplication of a parent against their child" is qualified to refer to the child who is excessively disobedient.

The mother should be advised gently and kindly to cease supplicating, while being keen to please her and avoid anything that might anger her.