There's only Mother Nature because Pitch only has one child. The others people like Cupid, Leprechaun ect haven't appear in the books or movie. So there's shouldn't be a page for them since we don't know of they exist in The Guardian of Childhood series. While the leprechaun was mentioned in RotG, we don't have any information on them. Until they make a more formal appearance in the story then we will add them to the wiki.

There is only "Mother Nature", not "Father Nature". Are you sure you don't mean "Father Time"?

In the Guardians of Childhood series, it is theorized that Ombric may be "Father Time".