My name is ***** ***** I have been a Vet tech for 35+ years. I would like to try and assist you.
To get your Hedgehog warmed up, try a heating pad on low under the blanket. The overhead light is fine, but you need an ambient temp of 76* to be optimal. Hibernation may have been what was happening, but that is a dangerous time for Hedgehogs in captivity. We need to keep her awake.
As far as the white eye, this could be from an abrasion from her siter or it also can indicate a Bacterial infection.
With all you have said about recent behavior, her being cold and the white eye I have to suggest a Vet visit with an Exotic Vet familiar with Hedgegogs.
These animals are what is considered a prey animal and they have learned to hide illness well. When this happens they can slowly decline until they can no longer hide being sick. It is important to catch things early
Please hit reply to discuss this information. I am here to help. This link should help you locate some Vets who can treat your Hedgehog:
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