Is the marriage contract considered null and void if the fiancée concealed her real age from a suitor younger than her, fearing that the marriage would not be completed or that it would lead to divorce?

A woman's concealment of her true age does not affect the validity of the marriage contract, nor is she obligated to inform the suitor of it unless he asks her. If she is asked and she lies, her action is haraam (forbidden), but it is not considered among the defects that establish the right to annulment according to the majority of scholars.