There is something very symbolic, poetic and freeing about a birdcage.
One of the most beautiful dreams I ever had was of Susan's bedroom in their castle in Narnia. The rafters were sculpted ivory and there were rainbow colored birdcages hanging from them. The walls were wall-papered with a cream colored paper with tiny red birds flying. She had a red canopy on her bed and a huge sea-green chest at the foot of it.
This is where I'd usually comment on some book I'm reading, but I'm not going to.