All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His Slave and Messenger.
It is not permissible for the husband to dispose of his wife's property without her permission and consent; the Prophet said: “The property of a Muslim is not lawful (for anyone else to take it from him) unless he gives it with his own proper consent.” [Musnad Ahmad]
Besides, the husband is obliged to provide for his wife and children as we have clarified in Fatwa 137523. Therefore, he is obliged to provide for the needs of her and their children. He is also obliged to be just between her and his other wife in regard to financial support and staying overnight with them. For more benefit, please refer to Fataawa 174179 and 88825.
If a wife is clearly harmed by her husband, she has the right to ask for divorce and it is permissible to encourage her to seek divorce from him if this is not done with the objective of spoiling the relationship between them. However, one should first of all endeavor to reconcile between them as there are great harms in divorce, especially for the children.
Nonetheless, if she accepts the situation with her husband, then interfering between them would be spoiling the relationship between them, since these are her own rights and she has renounced them.
Allaah Knows best.