The World Federation One Stop Fiqh

Ruling 2398

If a father or paternal grandfather marries his non-bāligh son/grandson to a girl, in the event that the son/grandson does not own any property at the time of the marriage contract, the father or paternal grandfather must provide his wife’s dowry. The same applies if he does own some property but his father or grandfather acts as guarantor (ḍāmin) for the dowry. Apart from these two cases, if the dowry is not more than the standard amount given for a dowry (mahr al‑mithl), or if a matter of primary importance necessitates that the dowry be more than the standard amount, then his father or grandfather can pay the dowry from the property of the son/grandson. Otherwise, they cannot pay more than the standard amount from his property, and it would only be valid if he accepts this after he reaches bulūgh.