Is it permissible to give zakat to a relative who is studying at a distant university due to the high tuition fees of nearby universities, knowing that he works to support himself and his siblings are unable to help him?

It is permissible to give zakat to deserving relatives, and this is better than giving it to others, provided that the relative is poor or needy, and not someone whose financial support is obligatory upon the zakat-giver (such as ascendants and descendants). If these conditions are met, it is permissible to give them from zakat to cover their needs, including completing permissible and beneficial studies.