What happens if a deceased person's religious burial requirements conflict with what surviving family members want?

There's no single rule that automatically resolves this - whoever holds legal authority over disposition of the body, generally the estate trustee, or the person entitled to act as administrator if there's no will, must consider the deceased's wishes, including religious requirements, but final decision-making authority rests with them, not any one family member. Religious burial requirements are often time-sensitive in their own right, since some traditions call for burial within a very short window, adding real pressure on top of an already difficult disagreement.

In practice, most of these situations get worked out through direct discussion, sometimes with input from a religious or community leader who can explain the requirements to family members who may not share the same view. Where a genuine dispute can't be resolved this way, legal advice can help clarify who actually holds the authority to decide, and, in a serious enough case, whether asking a court for direction is realistically achievable given how quickly burial arrangements typically need to move.

If you know this kind of conflict could arise in your own family, discussing your wishes clearly in advance, and appointing an executor you trust to carry them out, does more to prevent it than the will's wording alone.