What a lovely surprise! Hedgehogs can move fast, so maybe your cat chased it indoors.
I would contact a local sanctuary and get some advice.
From Snuffle Lodge Hedgehog Rescue
Hibernaculums are the winter nests hogs use to hibernate – they are usually very well built, but could be indoors, under sheds, in compost heaps, even in newly built but unlit bonfires. The key here is to leave well alone – it can be dangerous for hogs to be woken from hibernation early. If you want to help your dozing hedgehog, please leave a shallow bowl of water and some dry cat biscuits out – hogs do stir occasionally for food, so these treats will be very welcome.
British style conquers on this occasion.


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