Sahih al-Bukhari 3774
Narrated Hisham's father:
When Allah's Messenger (ﷺ) 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.‏