Sahih al-Bukhari 5133Book 67, Hadith 69
حَدَّثَنَا مُحَمَّدُ بْنُ يُوسُفَ، حَدَّثَنَا سُفْيَانُ، عَنْ هِشَامٍ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ أَنَّ النَّبِيَّ صلى الله عليه وسلم تَزَوَّجَهَا وَهْىَ بِنْتُ سِتِّ سِنِينَ، وَأُدْخِلَتْ عَلَيْهِ وَهْىَ بِنْتُ تِسْعٍ، وَمَكَثَتْ عِنْدَهُ تِسْعًا.
that the Prophet (ﷺ) 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).