Nu'man bin Bashir (May Allah bepleased with them) reported:
Messenger of Allah (ﷺ) said, "The believers in their mutual kindness, compassion and sympathy are just like one body. When one of the limbs suffers, the whole body responds to it with wakefulness and fever".[Al-Bukhari and Muslim].
Arabic/English book reference: Book 1, Hadith 224