I think being very empathetic and intense can even make it difficult to be as kind to siblings as one would like. My daughter gets so tense after school (from being a perfectionist all day) that I think she feels like she can relax with her brother and take out her frustrations with someone who will put up with it. She knows intellectually that it's wrong and we have tried a wide range of coping techniques, but it's very difficult when she has had a stressful day (and something we work on every day).

I think I did something similar to my parents as I didn't have siblings; it can't have been fun for them.