Ymbrynes who can transform into flightless birds usually care for peculiar children from wealthy, respectable families- both families with histories of peculiarity and families who see the first drop of peculiar blood in their children. These children's parents wouldn't dream of allowing their child to inhabit the same loop as poorer children.

When the threat of hollows and wights came to be in 1908, there was panic especially among these wealthy loops; they thought that the wights would come for them first because they were so well-connected.

Miss Lyrebird is one of these flightless ymbrynes who maintains and looks after a loop for wealthy peculiar children. She set her loop on August 18, 1908. Miss Lyrebird is different from other flightless ymbrynes; she allows peculiar children who don't come from a wealthy background to stay in her loop, though they must stay at a different house and be servants to the others.