Is concealing information about the illnesses of the bride's sisters—knowing that the bride herself is not afflicted—considered deception, or is such an action permissible?

Scholars have differed regarding the defects in marriage that must be disclosed. The more sound opinion is that any defect which causes one spouse to be repelled by the other, and prevents the realization of the marital objectives of affection and mercy, necessitates the option (of annulment) and establishes the right to فسخ (annulment) if it was concealed. The criteria for defects that must be disclosed to the suitor are three: that the illness affects marital life or is repulsive due to its appearance or odor, and that it is real and permanent, not imaginary or temporary. There is no sin upon someone who did not know about the illness and therefore did not conceal it.