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.
My dad spent 40 years mastering his craft, and last week someone half his age told him how to eat.😠


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