Narrated by An Numan bin Bashir(Radhiallaho anho):
Allah’s Messenger (sallallaahu ‘alaihi wasallam) said “You see the believers as regards their being merciful among themselves and showing love among themselves and being kind, resembling one body, so that, if any part of the body is not well then the whole body shares the sleeplessness (insomnia) and fever with it.”
Sahih Al-Bukhari Vol. 8 : No. 40

Being merciful toward people
Narrated by Jarir bin Abdullah (Radhiallaho anho):

Allah’s Messenger (sallallaahu ‘alaihi wasallam)said, “He who is not merciful to others, will not be treated mercifully.”
Sahih Al-Bukhari Vol. 8 : No. 42

The superiority of the guardian of an orphan

Narrated by Sahl bin Sad(Radhiallaho anho):

Allah’s Messenger (sallallaahu ‘alaihi wasallam) said, “I and the person who looks after an orphan and provides for him, will be in Paradise like this,putting his index and middle fingers together.”
Sahih Al-Bukhari Vol. 8 : No. 34