your younger brother, will, was about 6 years old, he was pretty chaotic but other times he was quiet as a mouse,

You were in your room, sitting on your bed, you were just looking at your phone, you here a quiet knock on your door and then soon after, will, dashes into your room and sits next to you, he looks at your phone, probably wanting attention or to watch what you were looking at. He was probably just lonely at the moment..