Is a man permitted to prevent his wife from spending the night at her family's home if he agrees to her weekly visits, and she is not alone in the house, as his mother and sister are with her?

There is no sin in preventing one's wife from spending the night at her parents' house. However, since the husband is traveling and there is no harm in her spending the night with her parents, and she desires to do so, it is preferable to grant her permission to foster love and affection.