Is the wife entitled to prevent her husband's brother from entering her home due to a dispute that occurred between them, given the husband's refusal of this and his setting boundaries for their interaction?

If the wife intends to prevent the brother from entering the house absolutely, even in the presence of the husband, then this is not her right, as it involves causing mischief and cutting off kinship ties. However, if she intends to prevent him in the husband's absence due to the lack of a mahram (unmarriageable kin), then this is a correct and religiously required intention. The wife is advised to overlook what happened between her and her husband's brother, and to be an aid to her husband in maintaining his kinship ties.