Is it permissible to bring an ashtray to one's father or guide him to it under the pretext of cleanliness? And is a father's supplication against his son acceptable in this case?

Smoking cigarettes and assisting in their consumption are forbidden. Obedience to a parent in this regard is not obligatory, based on the Prophet Muhammad's (peace be upon him) saying: "There is no obedience in sin; obedience is only in what is good." If the parent requests an ashtray, and providing it assists them in smoking, such that they would refrain from smoking without it, then it is not permissible to bring it. However, if your refusal does not make a difference, and they will smoke in any case, then there is no harm in bringing the ashtray. A parent's supplication against their child unjustly is not answered, based on the Prophet's (peace be upon him) saying: "The supplication of a servant continues to be answered as long as he does not pray for a sin or for the cutting off of kinship ties." Praying against one's child unjustly is among the prohibited sins. Furthermore, a supplication made in a state of anger and vexation, where its true meaning is not intended, is not answered, which is a mercy from Allah to His servants. The hadith (definition) "There are three supplications that are answered... and the supplication of a parent against his child" is conditioned on the child being unjust or disobedient.