Is it forbidden for a father to buy gold for his newborn daughter—from his own money—so that she is like her elder sister, whom the grandmother gifted gold, especially given the father's inability to buy gold for his other children?

Justice must be observed among children in gifts and donations, but regarding maintenance (nafaqa), each child is given what they need. Therefore, any gold given to a girl falls under the category of maintenance if it is commensurate with her need, and it is not obligatory to give the male child something similar, or to give the sister who already possesses something similar.

Sheikh Ibn Uthaymeen clarified that equality in spending means giving each one what they need. So, if a daughter needs jewelry worth a thousand riyals, and a son needs a ghutrah and a skullcap worth a hundred riyals, then justice is to fulfill the needs of both without equating the monetary value. It is also not obligatory to buy a car for a son who needs one; rather, the car can be bought and owned, and the son can benefit from it.