If you have an older, drafty house, it can be kind of hard to keep temperature even and comfortable from room to room. We get a lot of inquiries here at Birdtricks about how cold is too cold for our parrots. The concerns generally stem from the knowledge that many parrot species originate from warm climates.
Astigmatism in only one eye may cause lazy eye (amblyopia) if present from birth. The affected eye does not 'learn' how to see because the brain ignores the signals it receives. Amblyopia can be treated with eye patching if diagnosed early enough, before the vision pathways in the brain are fully developed.
Medical Definition of Lazy eye. Lazy eye: An eye that diverges in gaze. A lazy eye is formally called strabismus. A lazy eye (strabismus) can be due to esotropia (cross-eyed) or to exotropia (wall-eyed). The danger of the condition is that the brain comes in time to rely more on one eye than the other and that part of the brain circuitry connected to the less-favored eye fails to develop properly, leading to amblyopia (blindness) in that eye.