When
Muhammad was about 53 years old he was doing a 9 year old child:
http://www.searchtruth.com/searchHadith.php?keyword=aisha+nine+years&translator=1&search=1&book=&start=0&records_display=10&search_word=allNarrated aisha:
The Prophet engaged me when I was a girl of six (years). We went to Medina and stayed at the home of Bani-al-Harith bin Khazraj.
Then I got ill and my hair fell down. Later on my hair grew (again) and my mother, Um Ruman, came to me while I was playing in a swing with some of my girl friends. She called me, and I went to her, not knowing what she wanted to do to me. She caught me by the hand and made me stand at the door of the house. I was breathless then, and when my breathing became Allright, she took some water and rubbed my face and head with it. Then she took me into the house. There in the house I saw some Ansari women who said, "Best wishes and Allah's Blessing and a good luck." Then she entrusted me to them and they prepared me (for the marriage). Unexpectedly Allah's Apostle came to me in the forenoon and my mother handed me over to him, and at that time
I was a girl of nine years of age. (Book #58, Hadith #234)
Narrated Hisham's father: Khadija died three years before the Prophet departed to Medina. He stayed there for two years or so and then he married 'aisha when she was a girl of six years of age, and
he consumed that marriage when she was nine years old. (Book #58, Hadith #236)
Narrated 'aisha: that the Prophet married her when she was six years old and
he consummated his marriage when she was nine years old, and then she remained with him for nine years (i.e., till his death). (Book #62, Hadith #64)
Narrated 'aisha: that the Prophet married her when she was six years old and
he consummated his marriage when she was nine years old. Hisham said: I have been informed that 'aisha remained with the Prophet for nine years (i.e. till his death)." what you know of the Quran (by heart)' (Book #62, Hadith #65)
Narrated 'Ursa: The Prophet wrote the (marriage contract) with 'aisha while she was six years old
and consummated his marriage with her while she was nine years old and she remained with him for nine years (i.e. till his death). (Book #62, Hadith #88)