Twin babies

I am the only one who always knows who they are, that is, which one is which. Ian knows. But even now he mixes them up occasionally. They have no idea that no one knows if they are Greta or Carmen. I always let friends and visitors know what color each one is wearing that day, so that they can know who they are holding or to whom they are speaking. The babies have no idea that people ask every time, "Is this Carmen or Greta?" They do know that they are with each other all day and all night, every day and every night. They know that they feed from the same breasts and sometimes switch places in the middle of feeding. They share their blankies. They pass toys to each other from their cribs. They kiss each other when the other one cries. They learn new words and new tricks from each other. They fight over toys and push and hit each other too. They don't know what it is like to be apart. And I can't imagine that they would wish to be apart, not now. I'm not even sure if they understand that they are two people. They just know they go together and that is how their world works.