Is merely greeting an unbearable sister sufficient to avoid severing kinship ties, and is the one who does so considered among those who maintain their family relations?

The Sharia commanded the upholding of kinship ties (Silat al-Rahim), but it did not specify a particular method or extent for it. Rather, the reference in this matter is custom. Kinship ties are upheld through visiting, contacting, corresponding, and exchanging greetings (salam). There are degrees of upholding kinship ties; the lowest is to avoid abandoning them and to maintain connection through speech, even if only by exchanging greetings. The nature of upholding kinship ties varies according to ability and need; some aspects are obligatory and some are recommended. One who maintains some degree of connection is not considered a severer of ties. However, one who falls short of what they are capable of is not considered a maintainer of ties. Upholding kinship ties with a Muslim who is openly disobedient (fasiq) does not necessitate harmful mingling, and it is permissible to shun them if a benefit results from it. Upholding kinship ties is not a matter of reciprocation, for the one who truly upholds ties is he who connects with his kin even when they sever ties with him.