Is it permissible for the mother of the recently deceased to attend her son's wedding, which was postponed until after her 'iddah ends, and does holding the wedding during this period violate Islamic law?

A woman observing the 'iddah (waiting period) after her husband's death is obligated to observe mourning (ihdad) for four months and ten days. This includes refraining from adornment and perfume, and only going out during the day for necessity. She must not spend the night anywhere but her own home. There is no objection to holding the wedding on its scheduled date, and the mother can attend it, provided she avoids adornment and perfume, and spends the night in her own home.