The ruling on giving zakah to the questioner's mother

Question:
May Allah reward you with the best reward for us and for the Muslims. Umm al-Salih says in her question: “Honorable Shaykh, may Allah keep her safe, my mother (may Allah preserve her) is divorced from my father (may Allah have mercy on him), and she has no income at all. She has three children, but they do not give her any money, even though they hold high positions. I say that I am taking care of her and providing her with a monthly allowance of two thousand riyals per year, totaling twenty-four thousand riyals. A long time ago, I asked one of the brothers about this, and he said it is permissible to count that as zakah. Do I consider my mother’s (may Allah preserve her) expenses as zakah? And if the answer is no, do I have to pay zakah for the previous period?”

Answer:
Yes, zakah is not permissible for the father or the son. It is not permissible from the descendant to the ancestor, nor from the ancestor to the descendant. What you did is considered maintaining family ties, not zakah. So you must pay the zakah for the past periods. Yes.