Is a wife entitled to secretly take money from her husband to meet her needs and the needs of her children, and what is the ruling on the money she has taken previously?

A husband must spend on his wife and children equitably. If he is parsimonious, then it is permissible for the wife to take from his money, without his permission, what suffices her and her children equitably. However, if she takes more than the obligatory maintenance, then this is impermissible, and she must repent and return the money to him or seek his forgiveness.