A helpless newborn fox grows into a confident young cub in this heart-melting video.
Volunteers gave her a teddy bear to play with, which demonstrated how fast she grew.
It's unclear exactly how the cub ended up at the foundation's veterinary hospital in the southern English town of Leatherhead, Surrey, but the charity said it has since released her back into the wild.
Volunteers filmed the footage in 2014 but posted it to YouTube on Wednesday, and it has already gone viral.
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