RELATIVES are those who are related to you through blood and close ties; such as the brother, the uncle, the aunt, or their children. Everyone who has a tie of relation with you has certain rights upon you in accordance with how closely they are related to you. Allah said regarding this: “And give to the relative his right.” (Qur’an, 17:26). Allah also said: “And worship Allah alone, and do not setup any partner to Him in worship, and be kind and good to the parents, and to the relatives.” (Qur’an, 4:36)
So it is obligatory upon everyone to treat his relatives in the best possible manner, and to support them in accordance with their needs, and what they seek of help and support. And this is what is enjoined by the Shariah, the ‘Aql (sound reasoning) and the Fitrah (natural disposition).
There are several textual evidences encouraging and urging Silat-ur-Rahim (joining the ties of kinship). The Prophet (peace be upon him) said: “Whosoever believes in Allah and the Last Day let him keep the ties of kinship.” (Al-Bukhari, no. 6138). For more read here.