Is it permissible for the husband to ask his wife to waive her right to custody in exchange for khulʿ, and is what he is doing considered an injustice? And is it permissible for the wife to request a divorce due to being deprived of seeing her child?

Separating a husband from his wife's mother and child is a grave evil. The Messenger of Allah, peace and blessings be upon him, warned that whoever does so will be separated by Allah from their loved ones on the Day of Resurrection. If the marital relationship deteriorates, then they should either separate through divorce or khul'. Custody is a right of the mother by consensus, as long as she does not remarry. Depriving a mother of her child is a greater sin than taking her wealth. Given the frequent absence of religious deterrents and Sharia courts, it might be most appropriate to waive custody in exchange for obtaining a divorce, because obtaining some rights is better than losing everything. The oppressed will be rewarded for their patience, and Allah will elevate their status. Allah Almighty will bring together those who dispute on the Day of Resurrection.