We sometimes don't understand the kind of relationship we share with our brothers or sisters. Some of us may find them to be bullies and sometimes we are the ones who are the bullies. Maybe you would like to understand better how the different sun signs react in different situations under different circumstances. Taking a Sibling Compatibility test can help you know your siblings better and help you share a much more enriching and learning relationship. Being a brother or sister has its own share of fun and being able to understand your sibling better will only make this a more pleasurable experience.