Anas b. Malik(R.A) reported Allah's Messenger (may peace be upon him) as saying:" Neither nurse mutual hatred, nor jealousy, nor enmity, and become as fellow brothers and servants of Allah. It is not lawful for a Muslim that he should keep his relations estranged with his brother beyond three days." [Sahih Muslim Book 032, Number 6205]
Abu Muhammad Jubair bin Mut`im (May Allah be pleased with him) reported: Messenger of Allah (PBUH) said, "The person who severs the bond of kinship will not enter Jannah". [Al-Bukhari and Muslim]
The Prophet of Allah (sal Allahu alaihi wa sallam) said: "When a deceased person is laid in his grave, he hears the sound of the footsteps of people as they go away. If he is a believer, the prayer will stand by his head, the fasting will be to his right, alms to his left, and all other good deeds of charity, kindness to relations, and good behavior will be by his feet." [Ahmad]
Source: Emails from myhadithoftheday
