The Messenger of Allah ﷺ used to pray thirteen rakahs at night, then when he heard the call to the dawn prayer he would pray two short rakahs.
كان رسول الله ﷺ يصلي بالليل ثلاث عشرة ركعة، ثم يصلي إذا سمع النداء بالصبح ركعتين خفيفتين.
Bukhari narrated it in the chapter on tahajjud (1170) from Abdullah bin Yusuf, from Malik, from Hisham bin Urwa, from his father, from Ayesha, and he mentioned it.I did not find it in the Muwatta in the narration of Yahya Laythi, nor in the narration of Abu Musab Zubayri, nor in the narration of Muhammad bin Hasan Shaybani, so perhaps it is among the additions of Abdullah bin Yusuf, Abu Muhammad Tunisi, for he heard the Muwatta nine years before the death of Malik, so he came upon additions that were not encountered by those who heard it later.