My grandfather passed away two weeks before the wedding date. Should the ceremony be postponed?

There is no Shariah prohibition on going ahead with the akad; the decision to postpone depends on the family's emotional state and agreement. The obligation of mourning for a long period applies only to a wife whose husband has died, not to grandchildren or other family members. Many families choose to go ahead with a simple akad and postpone the big feast. This choice honours the deceased without delaying the marriage. Discuss it with your parents and the wali, especially those most affected. Offer prayers and charity for the deceased, and make the occasion simpler and full of prayer. See walimah.