Is it obligatory to give money to my parents for my sisters' marriages, or should I first spend it on Hajj for them?

If the parents have not performed the Hajj obligatory pilgrimage, they should accept their daughter's assistance in enabling them to perform it, even though the majority of scholars do not obligate them to do so. Imam Al-Shafi'i, however, holds the view that a person is obligated to accept what his child offers him to enable him to perform Hajj. If they refuse, then they should be obeyed in their request for assistance with the costs of their sisters' marriages.