Prophet Muhammad married a young girl with the name Aisha when she was six, and consummated the marriage when she was nine.
The source of the above information can only be the Hadiths books which are nothing but lies attributed to prophet Muhammad. It has no support in Quran. It does not make practical sense. Any person at the age of six is still a child who is incapable of taking crucial decisions which are essential for marriage under Quranic guidance, like taking solemn pledge, ascertaining mutual attraction, agreeing to the dowry (including adjustment thereto), ascertaining whether the opposite person is an idol worshipper or not and many other issues. Further, marriage involves taking serious responsibilities on the part of both the spouses concerning the upbringing of the family, which a child of the age of 6 or 8 or whatever is incapable of taking.
God commanded us in Quran not to accept any Hadith but the Quran. You will find a rich source of information regarding the corruption of Hadith books and how they insult the prophet Muhammed, insult God Almighty and insult this great religion on our web site at; http://www.submission.org/misconceptions/
Again, both marriage and divorce are based on choice and mutual agreement of both parties, the man and the woman (2:221, 4:24, 2:33, 4:35). A certain level of wisdom and maturity is needed to reach for agreements and to make decisions. The above claim documented in man-made history books of Hadith& Sunna, and others that prophet Muhammad married a nine years old child cannot be validated in the light of Quran. That myth is a direct violation of all the divine ethics to guard for the children and to preserve their innocence as in (24:58). It is also against the divine DECREE for a man and a woman to mutually agree with marriage or divorce.
[24:58] O you who believe, permission must be requested by your servants and the children who have not attained puberty (before entering your rooms). This is to be done in three instances - before the Dawn Prayer, at noon when you change your clothes to rest, and after the Night Prayer. These are three private times for you. At other times, it is not wrong for you or them to mingle with one another. GOD thus clarifies the revelations for you. GOD is Omniscient, Most Wise.