My sister is mentally disabled and I am her guardian. She receives an annual sum from the state. Is it a sin for me to spend some of it on myself?

Question:
He says: I have a sister who is ten years younger than me, and she is mentally disabled and knows nothing about the affairs of this world. My father passed away some time ago, and I am now taking care of her and providing for her, just as I would for one of my daughters. This sister receives an annual sum from the state, which is five thousand riyals. Is it permissible for me to add this to my own money and spend from both on everyone? May Allah reward you with good.

Answer:
May Allah reward you for your kindness to your sister, especially since her mental condition requires kindness. This is an obligatory duty upon you, and you will be thanked for it and rewarded by Allah (Glorified and Exalted is He) for it. As for the money the state pays her, that is her right, and she is to be provided for from it. Any surplus should be saved for her and kept for her, because she needs to accumulate and grow her money, so that Allah may put blessing in it and make her independent of people in the future. So you must save what is in excess of her expenses, keep it for her, and not mix it with your own money. Yes.