WATCH: Dog doesn't recognise owner after 23kg weight loss

This is the emotional moment a man who was in hospital for five weeks is totally unrecognisable to his beloved dog.

Willie the dog has been captured on camera wildly barking at the man sitting on a bench in the garden of their house, failing to realise that it’s actually his owner.

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The man had been in hospital for weeks suffering from an unknown illness and returned back to his house a whopping 23kg lighter.

However instead of greeting his owner with a warm welcome, Willie the dog is hostile and immediately treats him like an intruder.

In the footage Willie can be seen keeping a good distance from the man while friends and family try to coax him over.

While he has his trepidations, Willie eventually makes his way over to scope out who he is.

He inches closer to the man, holding his nose out before he finally gets within smelling distance.

And then the penny drops and Willie realises exactly who the man is.

Then the pair hug as Willie realises his owner has returned, running off to play in pure excitement.

The video was posted to Twitter by ‘Common White Girl’ and has since been viewed over four million times.

People were quick to comment on the video, with many claiming that it proves just how emotional dogs can be.

“Absolutely brilliant animals never forget,” one commenter said.

“Dogs are so precious and deserve the world,” another person said.

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