In this connection, the Guardian feels the necessity of bringing to your attention the fact that the validity of a Baha'i marriage is conditioned upon the consent of the two parties and their parents only. So that in case the other members of your family show any dislike or opposition to your sister's union ... their objection does under no circumstances invalidate it. Your parents' approval would be sufficient, even though all the rest of your family may violently oppose it.
March 31, 1937