I believe in chosen family, that we define ourselves by those we choose to use in our juxtaposition. Maybe it harkens back to the eternal battle of nature and nurture, between destiny and free will, but I'd rather believe that who we bring into our lives to share our days says more about ourselves than the woman in whose womb I was incubated, the accidental or planned siblings with whom I was raised.
I don't mean to assign undue value to very person in my life- some people are just distant cousins who I spent a nice summer abroad with, some are childhood pen pals from what seems like another planet, and some are your grandmother's sisters who you know you should respect but maybe don't understand all the reasons why. Nor do I intend to discredit that through the crucible of life the very person who slept in the top bunk your whole childhood is who you most undoubtedly would have chosen anyway or that the parent who sacrificed much will always be deserving of eternal gratitude and a call on Sunday.
The person who protects and teases, that's my brother. Some of my brothers share bits of my DNA, some do not. The person who commiserates and makes mischief is my sister. One of my sisters I washed in a tub when she was a baby, one washed me as an adult. The person who lent quiet strength, that is my mother. She was 50 when I was born.
Just like we can move into neighborhoods with nice neighbors, we can put ourselves in baskets on river banks and allow serendipity and bit of faith help us find our family.