Friendly and demonic. Terrifying and comforting.
Throughout my childhood, they were always watching over me, staring down into my room. Transformed by every gust of wind, a smile could turn threatening in an instant, and hungry fangs could just as quickly become a warm laugh. They were constantly shaken and warped and rearranged -- from face to face to ever-changing face.
Fuelled by my unconscious imagination and a quirk of the human brain, the leaves of the trees outside my window, together with the patches of sky between them, became a strangely shifting crowd of faces that I found endlessly fascinating.