Usually at least once in a person's childhood we lose an object that at the time is invaluable and irreplaceable to us, although it is worthless to others. Many people remember that lost article for the rest of their lives. Whether it was a lucky pocketknife, a transparent plastic bracelet given to you by your father, a toy you had longed for and never expected to receive, but there it was under the tree on Christmas... it makes no difference what it was. If we describe it to others and explain why it was so important, even those who love us smile indulgently because to them it sounds like a trivial thing to lose. Kid stuff. But it is not. Those who forget about this object have lost a valuable, perhaps even crucial memory. Becuase something central to our younger self resided in that thing. When we lost it, for whatever reason, a part of us shifted permanently.