Is it obligatory to carry out a wife's will that her son quit his job, and that her daughters not live with their husbands' wives?

Legally, this will is not obligatory to execute, whether it pertains to the son's work or the daughters not living with the sons' wives. This type of will does not serve a legitimate religious purpose, as long as the son's work is permissible (halal), and there is no harm to the daughters in living with the sons' wives.