Answer
Wa`alaykum as-salamu wa rahmatullahi wa barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
1- It is really a complicated and sensitive issue that requires wisdom and carefulness when dealing with. So, you need to consider your brother’s feelings and psychological well-being.
2- Make du`aa’ for your father’s forgiveness and help your mother maintain sincere repentance.
3- We can truly appreciate the extent of the shock your brother will undergo when he faces the truth, which has been hidden from him this whole time, but you can be wise and let him know gradually.
4- We are not in a hurry concerning this now because there are no urgent, practical aspects dependent upon this information.
Answering this question, Dr. Salah Al-Sawy, the Secretary General for the Assembly of Muslim Jurists in America (AMJA), said:
Your father (may Allah have mercy on him) did something good, and he also did something bad. It was good of him to keep your mother’s sin a secret and to help her repent and begin a new life of chastity, virtue, and purity.
What he did wrong, however, was to adopt a child that is not his and to claim that he is his own. That is one of the major sins, and it is absolutely forbidden by Shari`ah.
Almighty Allah says:
“Assert their relationship to their fathers; this is more equitable with Allah, but if you do not know their fathers, then they are your brethren in faith and your friends, and there is no blame on you concerning that in which you made a mistake, but (concerning) that which your hearts do purposely (blame may rest on you), and Allah is Forgiving, Merciful.” (Al-Ahzab 33:5)
Nothing is left now but the practical considerations of the whole issue. As for your brother and cousin’s marriage, there is nothing wrong with that, because the marriage is lawful in either cases — whether he is her uncle’s son or not.
As for you and your siblings’ transferring of a share of the inheritance to him as a gift or donation, there is nothing wrong with that, for your father’s estate will become yours in the future, Allah willing. What remains, however, is the matter of telling him about the reality of his situation.
I can truly appreciate the extent of the shock he will undergo when he faces the truth, which has been hidden from him this whole time, but you can be wise and let him know gradually.
We are not in a hurry concerning this now because there are no urgent, practical aspects dependent upon this information.
We ask Allah to be merciful to us and to you in that which is brought by fate. Your brother did well to flee to his Lord from these trials, so he found under His protection serenity and tranquility.
Do as he did, and you will see blessings and subtle grace from your Lord that would never have come to your mind!
Almighty Allah knows best.
Excerpted with slight editorial modification from AmjaOnline.com.