A small teenager

My daughter lives in a part reality/ part fantasy world. She goes back and forth between the two of them all day long. Anyway, we were in the bathroom brushing our hair (me, once; her, four thousand times) when she started talking about her "brother". First, she told me he was four years old, then she switched it and said, "really, he's a small teenager." It cracked me up trying to picture what she was picturing.