My concern is about this couple a Muslim man and his Muslim wife. The man was shia when he married a sunni in a temporary marriage due to administrative problems in their country. Then the man became a sunni and they married according to sunni law before a Qadi and two witnesses. The Qadi who gave the woman in marriage did not know that she was pregnant A marriage license was issued and they lived together for several years and had other children. Is this marriage valid? If not what should be done? What is the legal status of the first child (a girl?)

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

Temporary marriage was permitted for some time by the Prophet (Sallallahu Alaihi wa Sallam), then he forbade it and its permissibility was abrogated, so it became forbidden until the Day of Judgment. There is clear evidence for this.

The most explicit of these Ahadith is what is reported in Bukhari and Muslim that Ali, may Allah be pleased with him said: "The Prophet (Sallallahu Alaihi wa Sallam) forbade temporary marriage with women."

It is reported in sahih Muslim that Sabra Al – Juhani said that the Prophet (Sallallahu Alaihi wa Sallam) said: "O, people, I had given you permission for temporary marriage and now Allah has forbidden it until the Day of Judgment."

Ibn – Al - Mundhir, Iyad, Al – Khattabi and Qurtubi reported that there is a consensus of the scholars about this.

Therefore temporary marriage is invalid. However, the child born of this marriage will be named after the husband if he believes that this marriage is correct.

Normally he should not have married her until she gave birth to the child, and they should not have gone to the judge except with the permission of the guardian of the wife. When there is no Wali (guardian), or there is someone preventing the woman from marrying,  it is the judge who has the authority to approve her marriage.  

Anyway, due to what has occurred, the children are legally named after this man.

Ibn-Al – Mughni said in Al – Furou: "The child will be named after his father when there is doubt about the validity of the marriage and in every invalid marriage where there is a some doubt about its validity."

Ibn Qudama said in Al – Mughni: "If a woman in a marriage that is controversial, gives birth to a child, the child will be named after her husband". This is the opinion of Imam Shafii and Abu Hanifa.

The opinion of the Maliki school of thought on this issue is that the child should be named after his father.

Al–Baggi, of the Maliki school of thought, said in his in interpretation of Malik's Muatta that Ibn Habib said: "if no punishment is inflicted on any illegal sexual relationships resulting from a controversial marriage, the child is named after his father."

However, if there is deliberate sexual relationship without a controversial marriage, then the punishment is due and the child is not to be named after the father. This applies to the case when a man gets married while he knows that the marriage contract does not render the woman lawful Halal for him.

Sheikh al – Islam Ibn Taymiya may Allah be pleased with him said: "Any marriage that the husband thinks that it is permissible, and whereby he has sexual intercourse with the wife, then the child that is born thereafter is named after the husband, and they (father and child) inherit each other according to the opinion of all the Muslims". He stated that the family lineage is not bound with the permissibility of the marriage.

He also stated:

However, if a man marries a woman, and it is agreed that such a marriage is invalid or there are differing opinions about its invalidity, and the man has sexual relationship with her, then the child born of this marriage is to be named after his father, and they inherit each other according to the opinion of all the Muslims.

He gave examples about this: such as, the temporary marriage, a woman marrying herself without a Wali, or without witness, etc.

As regards the validity of the marriage, the correct opinion of the people of knowledge is that it is valid. Because the Hanafi and Shafii school of thought permit the marriage of a man to a woman he made pregnant from Zina.

Since the marriage of a man to a woman who is pregnant from Zina is permitted, then it is more appropriate to permit a marriage in which the wife becomes pregnant in a controversial marriage.

However, the Maliki School of thought consider the controversial marriage in which the woman is in a waiting period to be correct if the child is named after the husband.

As regards the Hanbali school of thought, they differed about whether this marriage is correct or not.

Al- Mardawi in Al- Insaf said: "It is more appropriate to marry her to the man who made her pregnant, because the waiting period is to declare the womb free from pregnancy because of another man, and here the man is the same person."

Allah knows best.