Sassy Siblings

It has now been almost 2 years since So gracefully took the role as sibling to Gavin.  Many a moment we have had where hitting is involved, hair is pulled, and screams are heard; however, I am very much aware of the love they have for each other and the support they give (when necessary).  Somehow they just know that they can always count on each other, through thick and through thin. 

How does this naturally occur?  How do siblings just automatically know that they will do anything and love the other no matter what?  Gavin and Sophia seem to have it down to a science some days.  They attack each other one minute, tag team in driving me crazy in another, and laugh hysterically practically high fiving each other for their accomplishments in another.  Here is just a glimpse of their beautiful brother/sister relationship...my heart melts.