I told my son: If you kiss the head of that scholar, I will give you one hundred riyals. He did so. Is it obligatory for me to give it to him?

Question:
He says: Honorable Shaykh, may Allah grant you success. I have a young son who is ten years old. I told him, "If you go and kiss the head of this scholar, who is one of the great scholars, I will give you one hundred riyals." So he quickly got up and kissed his head. The question is: Do I give him the hundred, or is it obligatory for me to be fair between my children and give them the same, or do I withhold it from all of them?

Answer:
You promised this; this is a matter of a promise. If you want to fulfill the promise, give your children the same. If you do not want to fulfill the promise, you are not required to, because fulfilling a promise is not obligatory according to the majority. It is obligatory according to some scholars, but the majority do not say that fulfilling a promise is obligatory. Yes, especially if it leads to injustice. Yes.