What is the ruling regarding a wife who speaks with her mother in an inappropriate manner about her husband and his family, and her mother supports her in that?

It is not permissible to listen to a wife's phone call with her mother without their knowledge and consent, due to the warning of the Prophet (peace and blessings be upon him): "Whoever listens to the conversation of some people while they dislike that, or they flee from him, then molten lead will be poured into his ears on the Day of Resurrection."

The husband must guide his wife to the seriousness of speaking about the honor of Muslims, and that she must obey him in what is good, and that her mother has no right to interfere in a way that spoils their relationship.

If the wife's mother is corrupting her, the husband has the right to prevent her from visiting and speaking with her until the corruption ceases.