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.
If this woman remarries, she loses the right of fostering her daughter. Her fostering moves to the female who has more right in fostering her after her mother, like her grandmother from the mother’s side as clarified in Fatwa 84618. If there is no female who has more right in fostering her, or that there is someone but she renounced her right, or that there is a religious impediment in her, then in this case, you have the right to foster her (your daughter). However, some jurists conditioned when the fostering moves to the father or any other male relative, that there should be a female who is suitable to do the fostering with him, like a wife or a Mahram woman.
Moreover, the jurists stated that each spouse has the right to see and visit his/her children in case the right of fostering is for the other spouse. The spouse who has the right of fostering has no right to prevent the other from seeing the children. Therefore, if your wife prevents you from seeing your daughter, then she is wrong. Hence, you may take the matter to the court so that it would oblige her to allow you to see your daughter; for more benefit, please refer to Fatwa 125277.
Since the issue of fostering is a matter of dispute and the jurists differed in opinion regarding many of its issues; then it is more appropriate, in our view, to take your matter to an Islamic court because the decision of the judge is binding on both parties and it puts an end to dispute in such matters.
Allaah Knows best.