Mishkat al-Masabih 7 Fasting كتاب الصوم 131

وَعَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا قَالَتْ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِذَا دَخَلَ الْعَشْرُ شَدَّ مِئْزَرَهُ وَأَحْيَا ليله وَأَيْقَظَ أَهله

She said that when the last ten nights began God’s messenger prepared himself for religious exercises, stayed awake at night and wakened his family. (Bukhari and Muslim.)