Her original name is Maggie.
When Walter goes through a midlife crisis, he becomes devoted to the guru Harm'ny Lightbeard and his philosophy of lightness. Walter moves his entire family up to Harm'ny's village in the sky, Meriloft, so they can better study his teachings.
Act I Edit
Vella meets M'ggie while she is tending to some eggs. She will give Vella the Ladder if she asks to borrow it. M'ggie tells Vella about the various birds and on how Harm'ny Lightbeard removes the feathervator which was originally used to carry people down to the forest below.