He adopted a little girl, and her parents are telling him to give her back, but he fears she may be misguided if he gives her back. What should he do?
Question

A few years ago, my paternal uncle applied to an adoption agency, asking them to let him adopt a child. A few months later they answered him, saying that they had found a baby girl, and that he could take her. He and his wife have taken care of her for two years, and his wife breast-fed her, which means that the man is now a mahram to her. The problem now is with his parents, who went to an imam, who told them that it is not permissible for them to adopt a little girl whose parents are still alive. But in fact, her parents abandoned her, so how can they take her back? Moreover, the adoptive parents do not know the names of the birthparents, because the adoption agency does not give any details of the birthparents, as that information is regarded as confidential. Now the parents are threatening to disown their son if he does not give up the little girl, and they [the adoptive parents] do not know what to do. They do not want to give the girl back for fear that she may end up with a non-Muslim family, and he is also afraid that if he does not give up this girl, he will lose his parents.
Do the parents have the right to ask him to give up the girl, and is he obliged to obey them in that?
Praise be to Allah.Firstly:
In the answer to question no. 126003, we explained that the word adoption, as customarily used by people, may refer to two things:

Undertaking to raise a child and care for him, without changing his lineage (by changing his surname and attributing him to the adoptive “father”);
or undertaking to raise him and care for him, whilst attributing that child to the adoptive family (by changing his surname), and regarding him as one of them.

The latter was permissible at the beginning of Islam, then was declared invalid by the Qur’an.
The former is a righteous deed and is prescribed in Islamic teachings.
If the family of this little girl is not known, and your paternal uncle undertook to bring her up and take care of her, without attributing her to himself, then he has done a good thing.
Nevertheless, this little girl does not come under the same rulings as his own child in terms of lineage and inheritance.
If he adopted her and attributed her to himself (by changing her surname to his), as the girl would be attributed to her birth father, then it is not permissible for him to do that, and he must put it right by changing her name back and correcting it in official documents, so that she will not be attributed to him or inherit from him. He must also seek Allah’s forgiveness and repent.
The scholars of the Permanent Committee said:
What you have done of adopting the child referred to and registering him in official documents as if he is your child, so that he will inherit from you as if he were your son, is clearly wrong and is overstepping the limits set by Allah, as well as lying to the officials in your country and telling them something that is not true. Adoption [in this sense] is not permissible in Islam… What you have done does not make him your son or heir. You must repent to Allah, may He be glorified, and set things straight in the official records. May Allah forgive us and you for errors and sins, and may He grant you the best reward for bringing up this child and spending on him. If you bequeath any part of one third of your estate to him, then that is good, and if you give him a gift whilst you are still alive, that is better, if he is in need, so as to complete your kindness to him.
End quote from Fataawa al-Lajnah ad-Daa’imah (20/352).
Secondly:
With regard to naming a foundling girl, if her lineage is not known, she should be attributed to a name that reflects servitude to Allah, such as ‘Abdullah [slave of Allah] or ‘Abd ar-Rahmaan [slave of the Most Gracious], as if this was her father’s name; a similar name should be given in the place of her grandfather’s name. So she may be called, for example, Fulaanah [So-and-so] bint [daughter of] ‘Abdillah ibn [son of] ‘Abd al-Hameed, or any other good names.
The scholars of the Permanent Committee said:
It is not permissible for one who takes care of a foundling child to attribute that boy or girl to himself, because Allah, may He be exalted, says (interpretation of the meaning):
“Call them by [the names of] their fathers; it is more just in the sight of Allah”
[al-Ahzaab 33:5].
Based on that, the adoptive parent must cancel the naming of the child after himself in official documents. Instead, he can attribute her to a name that reflects servitude to Allah, may He be glorified, such as ‘Abdullah [slave of Allah] or ‘Abd ar-Rahmaan [slave of the Most Gracious], as if this was her father’s name; a similar name should be given in the place of her grandfather’s name.
End quote from Fataawa al-Lajnah ad-Daa’imah (18/161)
If her lineage is known, she should be attributed to it (and given a name that reflects that).
Thirdly:
The son should inform his parents about the ruling on this issue after correcting the child’s name, and tell them that it is prescribed in Islamic teachings for him to undertake to bring her up and take care of her, and that this does not come under the same heading as the type of adoption that is prohibited. He must explain that to them in a wise and gentle manner.
The son does not have to return the child to the adoption agency, because that would be placing the girl in danger, and because of the troubles that may result from that and the possibility of the child being misguided, unless her parents are still alive and are Muslims, and he can get in touch with them, and there is no fear of them harming the girl in any way. In that case, he must return her to her parents, and he will be rewarded for his previous kindness to her and his taking care of her.
His parents have no right to demand that he give her up and return her to the agency, and he is not obliged to obey them in that, because of the great evil and harm that may result from that. But he has to explain the ruling to them, and be kind to them as much as possible.
And Allah knows best.