Is it permissible, Islamically, to avoid a brother who is characterized by harshness, does not like good, and does not communicate with his siblings, and to merely treat him in kind?

The Shari'ah encourages affection and love among Muslims, and this is particularly emphasized among relatives due to the obligation of upholding kinship ties (silat al-rahim) and the prohibition of severing them. This is based on the Almighty's saying: "And fear Allah, through whom you ask one another, and the wombs (kinship ties)." The Prophet, peace and blessings be upon him, clarified the immense reward for upholding kinship ties and the punishment for severing them. Mere aloofness does not, by itself, constitute severing kinship ties. Connection (silah) can be achieved even through speech, such as exchanging greetings. This connection can have varying degrees, the lowest of which is refraining from abandonment. The one who severs ties should be advised gently and kindly, reminded of Allah, and help should be sought from those whose words they respect. You must not abandon them even if they abandon you, and do not cut ties with them even if they cut ties with you, so that you may attain the great reward. If you fear harm from them, cut ties with them in the aspect that causes you harm, but maintain ties with them in other aspects.