In The Name of Allaah, The Most Merciful, The Bestower of Mercy.

Severing the ties with relatives and boycotting them due to affairs of little importance is not permissible; rather it is obligatory to keep the ties of kinship, even if your relatives harm you personally. The true keeper of the ties of kinship is the one who maintains ties even if they (i.e. relatives) break it; as reported by Imaam Al-Bukhaari (rahimahullaah) and others on the authority of Abdullaah Ibn Amr Ibn Aas [radiyallaahu-anhu] that the Prophet [sallal-laahu-alayhi-wasallam] said, “The maintainer of the ties of kinship is not the one who returns kind treatment to his relatives when they treat him kindly; rather the maintainer of the ties of kinship is the one who, when his relatives cut him off, he maintains it”.

And (Imaam) Muslim reported in his Saheeh on the authority of Abu Hurairah that a man said, “O Messenger of Allah! I have relatives with whom I maintain ties of kinship, while they cut me off. I treat them kindly, while they are evil to me. They behave ignorantly towards me and I am forbearing towards them.’ He (sallal-laahu-alayhi-wasallam) then said: ‘If the (affair) is as you have stated, it is as if you were placing hot ashes on them and you will not cease to have a supporter from Allaah against them as long as you carry on doing that’”.

Source:Al-Mindhaar Fee Bayaani Katheer Minal Akhtaa Ash-Shaa’i’ah by Shaikh Saaleh Aala Shaikh (hafidhahullaah). Pages 80-81