Sayyidina Anas (RA) reported that Allah’s Messenger (SAW) said, do not sever ties of relationship, do not criticize one who is absent, do not despise anyone and do not be jealous of someone. But, be slaves of Allah, brothers mutually. It is not lawful for a Muslim to abandon his brother for over three days.”
[Ahmed 12074, Bukhari 6026, Muslim 2559, Abu Dawud 4910]