What is the ruling on giving Zakat al-Fitr to a needy mother who has no source of income or private dwelling?

It is not permissible to give Zakat al-Fitr to one's parents because their maintenance is obligatory upon the child. The child must provide accommodation for his mother if he is able. However, if the mother resides with her daughter and has no other provider, and the daughter wishes to give her Zakat al-Fitr on behalf of her husband and children, there is no harm in that, as it is not from the daughter's own wealth.