Sahih al-Bukhari, Hadith 3774 ⓘ
Narrated Hisham's father: When Allah's Messenger was in his fatal illness, he started visiting his wives and saying, "Where will I be tomorrow?" He was anxious to be in `Aisha's home. `Aisha said, "So when it was my day, the Prophet became silent (no longer asked the question).
حَدَّثَنِي عُبَيْدُ بْنُ إِسْمَاعِيلَ، حَدَّثَنَا أَبُو أُسَامَةَ، عَنْ هِشَامٍ، عَنْ أَبِيهِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم لَمَّا كَانَ فِي مَرَضِهِ، جَعَلَ يَدُورُ فِي نِسَائِهِ وَيَقُولُ " أَيْنَ أَنَا غَدًا أَيْنَ أَنَا غَدًا " . حِرْصًا عَلَى بَيْتِ عَائِشَةَ، قَالَتْ عَائِشَةُ فَلَمَّا كَانَ يَوْمِي سَكَنَ.
also referenced under: Book 62, Hadith 121 (In-Book) & Volume 5, Book 57, Hadith 118 (USC-MSA)