Sunan Ibn Majah, Volume 5, Book 37, Hadith 4294 (DarusSalam) ⓘ

It was narrated from Abu Sa’eed that the Messenger of Allah said: “On the day when He created the heavens and the earth, Allah created one hundred (degrees of) mercy, of which He placed one on earth, by virtue of which mothers show compassion to their children and animals as well as the birds show compassion to one another. And He kept back ninety-nine (degrees of) mercy. When the Day of Resurrection comes, Allah will complete this mercy.”

حَدَّثَنَا أَبُو كُرَيْبٍ، وَأَحْمَدُ بْنُ سِنَانٍ، قَالاَ حَدَّثَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ أَبِي صَالِحٍ، عَنْ أَبِي سَعِيدٍ، قَالَ قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ ‏ "‏ خَلَقَ اللَّهُ عَزَّ وَجَلَّ يَوْمَ خَلَقَ السَّمَوَاتِ وَالأَرْضَ مِائَةَ رَحْمَةٍ فَجَعَلَ فِي الأَرْضِ مِنْهَا رَحْمَةً فَبِهَا تَعْطِفُ الْوَالِدَةُ عَلَى وَلَدِهَا وَالْبَهَائِمُ بَعْضُهَا عَلَى بَعْضٍ وَالطَّيْرُ وَأَخَّرَ تِسْعَةً وَتِسْعِينَ إِلَى يَوْمِ الْقِيَامَةٍ فَإِذَا كَانَ يَوْمُ الْقِيَامَةِ أَكْمَلَهَا اللَّهُ بِهَذِهِ الرَّحْمَةِ ‏" ‏ ‏.‏