As long as there are people, there will be disputes. And unfortunately, the nastiest quarrels often happen amongst family members. Sibling rivalries being one of the most intense and severe.
When someone makes you feel rotten, it is actually futile to response in kind. An eye for an eye way of doing things are usually pointless. Life has taught me that it is best to take the higher ground. Staying calm, taking a step back, and just letting things simmer over are simpler ways to deal with most disagreements. It is an act of kindness to all those involved, especially towards oneself. Response in kindness, not react in vengeance. We all have just this one very short life. No repeats.