There's a unique bond between siblings that's easily noticeable if you're a sibling yourself.

Before I even approached these two, I could tell that they were brothers. Not from the way that they resembled each other, but because of the way they interacted. An eagerness to learn was written on the face of the younger one; it seemed that all he wanted was to make an impression on his older brother. I could feel their brotherly bond before I even fired the shutter.

All of a sudden, I remembered all of those moments growing up where all I wanted was to be like my brother.

If you have a brother or sister, consider yourself a lucky one.