Should the woman hand over the money that the deceased entrusted to her for her mother's and sister's Hajj expenses to the heirs, or should she carry out the deceased's will?

The money mentioned is considered a trust (wadi'ah) and transfers to the heirs of the deceased woman, because a will is not valid for an heir, nor can it exceed one-third of the estate. Similarly, if what was received from the deceased was a gift or charity, it becomes void upon the death of the giver or the one who intended to give charity before the recipient takes possession, just as an agency (wakalah) becomes void upon the death of the principal.