What do you think the bird symbolizes?

Taylor must deal with a bird that has flown into the house while the police and a social worker arrive. I tend to think the bird symbolizes the chaos that lurks outside the protections for Turtle. Although Turtle is safe with Taylor there is a wildness of the human world, personified by the bird, that remains outside.

On another level the frightened sparrow in the house could symbolize Turtles own feelings trapped in her nightmare.