Kitāb al-Muʾmin
Hadith 5757- وعن أب عبد اله (ع) قال: إذا التق المؤمنانِ كان بينهما مائة رحمة؛ تسع وتسعون لأشَدّهما حباً لصاحبه
57. It has been reported that Abu 'Abd Allah (a.s) said: When two believers meet, one hundred mercies are showered between them—ninety nine of these go to the one who loves the other more.