If you never fought with your brother or sister when you were growing up, were you even related? Fighting with your sibling is just one of life's many unwritten rules...
Most arguments would be triggered by things like borrowing stuff without asking, before breaking and/or losing those belongings, hogging the computer, ratting you out to your parents and just generally being a piece of sh*t.
In MOST cases, this will usually stop happening around your late 20s, however, some siblings just never stop arguing... forever. They are often the person you love to hate the most in the world, and it's often justified.
The good thing about all of this, is that a study now exists claiming that those who went through years of sibling rivalry actually become better people later in life.
The study, which was completed by the University of Cambridge, says that arguing with your sibling through your early years is beneficial for your mental and emotional development. You're basically training yourself in the art of handling your emotions.
Research for the study, entitled 'Toddler's Up', took a whopping five years to complete and observed 140 children between the ages of 2 and 6. And the results were surprising.
According to the study, sustained sibling rivalry could lead to relationship-building and behavioural issues later in life (Liam and Noel, anyone?), however milder forms are extremely beneficial and ensure healthy development through childhood.
We're not suggesting starting up an old beef with your sister or brother here, but this research does help with the guilt when thinking back to all of those silly childhood fights.
To read into the study some more, give it a read here, before thanking your sibling for helping you develop into such a great person.