2 JOHN VERSES 10 AND 11
“If anyone comes to you and does not bring this doctrine, do not receive him in your house or even greet him;
for whoever greets him shares in his evil works.”
READ THE CONTEXT IN VERSE 9
“Anyone who is so “progressive” as not to remain in the teaching of the Christ does not have God; whoever remains in the teaching has the Father and the Son.”
NOTE: Catholic faith is the ONLY ORIGINAL AUTHENTIC TEACHING OF THE CHRIST, therefore shunning a Catholic exJW using this text is pure heresy.
Is it okay to not have a relationship with a sibling?
https://www.catholic.com/qa/shunning-a-sibling
No, it is not “okay” to not have a relationship with a sibling. You have not offered any special circumstances to consider, so I can only say that, as a general principle, families are expected to maintain peaceful relations and to reconcile their differences. Jesus went so far as to warn those who refused to reconcile with a brother that they risked eternal damnation:
I say to you that every one who is angry with his brother shall be liable to judgment; whoever insults his brother shall be liable to the council, and whoever says, “You fool!” shall be liable to the hell of fire. So if you are offering your gift at the altar, and there remember that your brother has something against you, leave your gift there before the altar and go; first be reconciled to your brother, and then come and offer your gift (Matt. 5:22–24).
Jesus’ words here usually are interpreted to refer to fellow Christians, who are brothers in Christ. But in the first letter of St. John, the evangelist draws on an allusion to Cain and Abel, natural brothers, to make much the same point:
By this it may be seen who are the children of God, and who are the children of the devil: whoever does not do right is not of God, nor he who does not love his brother. For this is the message which you have heard from the beginning, that we should love one another, and not be like Cain who was of the evil one and murdered his brother (1 John 3:10-12).
If there are special circumstances that seem to indicate a need to distance oneself from a sibling, I recommend discussing the issues with a family counselor and/or a spiritual director. If there are lesser measures, short of shunning, that can be taken to ensure personal safety, then those lesser measures ought to be considered.
Shunned by Kingdom Hall
https://www.catholic.com/magazine/print-edition/shunned-by-kingdom-hall