I Have a Sister 我有一个妹妹
Father: Is the school closed today?
Son: No, Dad. I came home early.
Father: How did you do that?
Son: I told my teacher I had a new baby brother and had to come home and help you.
Father: But your mother has had twins. You’ve got a baby brother and a baby sister.
Son: Yes, I know, Dad. I’m saving up my baby sister for next week.