One is not sinful if he forfeits his right willingly
11-8-2013 | IslamWeb
Question:
Assalaam alaikum I wanted to know is there any sin on a person who waives their rights. E.g. if a woman who wants children but husband says no more, she goes along with what he says to keep the peace. Or if a person asks for financial aid from their parents and they refuse, but later she finds out they gave a large amount to two of her siblings? Should a person demand what they have a right to or leave it to reduce arguments and conflict between family? Thanks for any answer you can provide.
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad 
is His slave and Messenger.
With regard to your first question, the husband has no right to prevent his wife from having children as having children is a common right of both spouses. However, if the wife renounces her right to have children and obeys her husband in this regard, then she is permitted to do so and she is not sinful. But if agreeing not to have children is without a need, then this is not appropriate as having more children is one of the most important objectives of marriage in Islamic Sharee’ah.
As regards your second question about one parent gifting some children without gifting others, then this is injustice which is not permissible, and whoever does that is sinful. The parent, be it a father or a mother, is obliged to be just in gifting his/her children and he/she should not favor one child over others unless there is a valid reason for favoring him/her, like if he/she is poor and the like. So, it is permissible for a woman to ask her parents for justice if they are not just with her; but if she wants to keep silent in order to avoid dissension, then she is permitted to do so and she is not sinful. However, she should clarify to them that they are obliged to be just with their children and gift them equally; as favoring one of them over others is a sin in religion and it leads to hatred and dissension in general.
Allaah Knows best.