5-year-old: “You can’t sit here! It’s my house.”
4-year-old: (wide-eyed, moving to another chair) “Here?”

5yo: “Okay, you can sit there. This is my house, you understand?”
4yo: (chewing a biscuit) “Okay…”

5yo: “This house is mine, this chair is mine, this room is mine, this… this… whole world is mine!”
4yo: (stops chewing and stares)

5yo: “Do you know what ‘this whole world‘ means?”
4yo (staring): “No…”

5yo: “This house, the gate, the road outside, everything is ‘the whole world‘.”