Mary Poppins opens the door

Up in the sky a tiny spark hovered and swayed in the darkness.

What could it be...? Still they waited. And still the spark grew ever larger and brighter. Then suddenly Jane caught her breath. And Michael gave a gasp. Down came the spark, growing longer and wider. And as it came, it took on a shape that was strange and also familiar.

Out of the glowing core of light emerged a curious figure - a figure in a black straw hat and a blue coat trimmed with silver buttons.