Some people spend more wealth for their brothers and sisters than their own children and wife, this create rifts not only between the husband and wife but also between the family of the husband and his wife because she starts thinking that they are the reason for her misery.
Sheikh Saalih received a question from a similar wife who said that her husband spends money on his family but when she demands he says he is short of money.
Sheikh responded that your husband’s act of spending on his family is a good act and it should be appreciated but his negligence for you is unislamic and should be accounted for.
If he fails to fulfill the need of the wife then the wife has the right to take from husband’s wealth without his permission. It is not called stealing because in husband’s wealth there is the right for the wife and her children, and if he fails to give the right then the wife can take it by herself.