The term "identical twin" conjures up images of a cloned pair, with exactly the same features and personalities. Able to switch roles at will, with none the wiser. Perhaps in the movies, but not in my house.
I've been mocked by friends and family since their birth, rambling off their physical differences, though subtle, so that each could be distinguishable as the independent little beings they are. I argued vehemently that they were fraternal twins up until the day I received DNA results when they were 15 months old stating they were indeed, monozygotic/identical twins.
Side note: in my defense, Jaeda's hair was brown at birth, and Tristyn's was blond. In twin pregnancy speak, they were DI-DI (dichorionic, diamnionic) which means they each had their own "apartment" as my perionatologist so eloquently put it - this is somewhat rare for identical twins, with only 8% of identical twins growing in the womb this way.
I think the answer lies in the simple equation of child and parent. As I write this, I'm on the floor in the hallway outside the bathroom, watching my girls as they play in the bathtub. Their forms so familiar to me that I can distinguish them at a glance, even if they aren't facing me. I notice each new mark and mole, and know each scream, squeal, giggle and voice from the other. I know the temperment of each one and how she will react when I tell her that "we don't jump in the tub". I have never known such intimacy. Such profound familiarity...
My husband and I still get odd looks when explaining there is something one twin likes that the other doesn't, as if that can't be.
They may have the same DNA, but they aren't the same person.