Is there a Sharia impediment to a traveler favoring his brothers and their sons with gifts over his married sisters, despite his knowledge of his sisters' displeasure, and that he is in debt and does not possess sufficient money to equalize, and that his brothers offer him more gifts and assistance than his sisters?

The Shari'ah commanded justice in giving gifts among children. It is desirable for a brother to strive for the unity of his siblings and not to prefer some over others. If some of your siblings show you kindness, reciprocate with kindness, for the Prophet, peace and blessings be upon him, said: "Whoever does you a favor, repay him." Be careful not to inform those whom you were unable to give similar gifts, and give them whatever you can. Be sure to accommodate everyone with your good manners and cheerful face, for the Prophet, peace and blessings be upon him, said: "Indeed, you will not be able to accommodate people with your wealth, but you can accommodate them with a cheerful face and good character."