Video Shows Shelter Dog's Joy as Adoptive Family Returns - but They Want Another Pooch

Zuzu was wagging his tail when he thought his adoptive family had come back for him.

A shelter dog's joyous moment quickly turned to devastation as her owners arrived at the care center, but not for her.

Zuzu, the 2-year-old German shepherd mix named after the girl from It’s A Wonderful Life, became an internet sensation Friday after a volunteer at Downey Animal Care Center posted video of the dog crazily wagging her tail as her previous owners came to her temporary home.

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But the family had only come to get another dog.

After the video was posted on Facebook, comments were abundant.

“Appalling!!!! They should not be given another dog!!!!,” wrote one person.

“How someone could ever do this is beyond me,” was another.

The dog was taken to the animal care center in Los Angeles on Thanksgiving. Prior to seeing her owners, she was subdued and scared and then her family came and she lit up.

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Trainer Janey Chapin told Inside Edition: “It's a heart-wrenching story of dog that's unwanted. She approached the fence and just started wagging her tail, barking at them. You could tell instantly that she knew them.

“We asked if family was there to reclaim her and they said no it they didn’t want her.”

She says the family complained Zuzu had become depressed after another pet in the family died.

But now, it looks like Zuzu will be getting a happy ending as a rescue facility will be taking the canine in. She will be up for adoption shortly.

Watch: Partially Blind Dog Gets a New 'Leash' on Life After Being Adopted: 'He Seems Real Content'