The plots developed organically, naturally. From Heather came the idea of a gross man who would find himself pregnant, - the theme of "Bread for Toggle". Also from Heather came the initial idea of a powerful old woman whose soul was captured in a box - a box that was then bound tight with briar. She actually dreamed this, and her husband, Gary, who wrote all the fables, was inspired by her dream. This, of course, was the origin of "Grandma's Soul". There were other strange happenings surrounding the genesis of these tales. The story called "The Blossom Maker" was written in just two hours, as if the writer was taking dictation from a spirit.
Simply by looking at the blossom on the trees, together with the experience of being husband and wife during their first spring together, led to stories which needed to be written. In fact, Heather and Gary were so inspired in those days, it is perhaps a valid question to ask why more tales were not created.
We can suppose the only answer is that they came as if by magic, and magic must always have a beginning and an end. Its power is a blessing, but it is finite.