What is the ruling on having a guard dog inside the house that roams freely within it? Is it permissible to fast, pray, and recite the Qur'an in a house where there is a dog? And what is the ruling on a wife leaving her husband's house during Ramadan because of the dog's presence?

It is not permissible to bring dogs into homes without a need. If there is a need to keep a dog for guarding, it must be kept away from the house's furnishings. The prayer is valid in a place that has not been touched by the impurity of the dog. As for fasting and reciting the Quran, the purity of the place is not a condition for them. It is advised for the husband and his family to clarify the Sharia ruling.