I say, and with God's guidance: The principle is that all our deeds, if they are due to the upbringing of our parents, their reward is attributed to them; because they are considered part of their efforts. However, if one dedicates an act of worship, such as prayer, recitation of the Quran, or fasting, to the parents, by offering the reward of it to the parents or others, then it belongs to them, and God Almighty will not deprive the one who performs it of the reward accordingly; because God Almighty is the Most Generous of the generous, and God knows best.