Honestly, the more I think about it, I think her mind made that baby’s eyes disappear. Maybe as a way of coping? The thing that makes us love humans and animals alike, are eyes. She wiped out his eyes to save her sanity. Although, not working there would have probably helped with that.
I was thinking that she put forth a “justification” for the killing of the baby.. i.e. a deformity. In her mind, it relieves part of the “guilt”. The fact that she defined a newborn’s baby’s crying as “alien”... says a lot to me.