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.
The jurists stated that a wife who has children from her ex-husband is not permitted to make them live with her new husband except with his consent. If he does not agree, it is not permissible for her to let her children [from another husband] dwell with them. This is the view of the four schools of jurisprudence. However, the Maaliki School makes an exception, it said that it is not permissible for a husband to prevent his wife from letting her children dwell with him if he knows about this before the consummation of marriage, or that he did not know about it but the children have no one to sponsor them. But if he did not know about them and they have someone to sponsor them, then the wife has no right to make them dwell with them [in her new husband’s home].
Therefore, according to the view of the Maaliki School, if your husband knew about this girl when he married you, or that he did not know about her but she has no one to sponsor her, then he is religiously obliged to agree that she would live with you.
Hence, if the religious right for keeping your daughter with you in your home is confirmed to you, so we advise you to discuss the matter with your husband in a nice way in the light of what we mentioned. If he agrees, then this is what is required. However, if he insists on refusing, then you should look for another means, like sending her to her father if he is a trustworthy Muslim who would keep her safe and provided he has a female with him who is suitable to foster the girl like a wife or a female Mahram. Or, you may send her to the mother of the father [her grandmother] if she is Muslim and trustworthy. If you do not find any solution, then you may take the matter to one of the Islamic centers so that they would study the matter and help you in finding a solution, among which is divorce if it becomes clear that it is the best solution.
Finally, it should be noted that you should not leave any of your children with your parents as long as they are non-Muslims as they [parents] may spoil their religion.
Allaah Knows best.