Is it permissible to give food from the home and excess provisions to the poor on behalf of the mother, without the knowledge of the father and sisters, given that the questioner knows her father will object because he is stingy, and will this charity be accepted?

Filial piety is an obligation, and disobedience to parents is a grave sin. Describing a father as stingy is a form of disobedience. It is not permissible to give a father's money to the poor or others without his knowledge, even if it is for charity on behalf of the mother, because in such a case, the charity would not be accepted.

However, it is permissible for a mature daughter to give charity on behalf of her mother from her own money without her father's knowledge.