A dog, who had known nothing but cruelty's life, changed when she was fostered, and now Peanut Butter the pit bull cross has found her forever home.

Mady O'Reilly, a volunteer and foster carer with Metro East Humane Society in Edwardsville, Illinois, told Newsweek she took Peanut Butter into her home after she arrived into their care in May after surviving a horrific dog attack. The owner surrendered Peanut Butter after she was attacked as they didn't want to deal with her injuries.

"Peanut butter first arrived at Metro East Humane Society in late May after surviving a dog attack," O'Reilly said. "The attacking dog was unfortunately shot. Her owner relinquished her to Alton Animal Control to deal with her injuries. Animal control officers reached out to us for assistance, and we said, 'Yes,' so she came to us the next day.

"She was traumatized and in total shock when she came in after going through all of that. She was practically catatonic on the surgery table during her initial clean-up and exam, which you see at the start of the video," O'Reilly added.

The footage, shared to her TikTok account @oreillymady, starts with Peanut Butter being treated at the vets, looking, as O'Reilly said, "catatonic". Barely moving or looking at her rescuers, the dog is then brought into a kennel in a blanket, where a choke chain had to be cut off her with bolt cutters as her neck had become so swollen from the attacks.

"Her back right foot was mangled, and she had multiple puncture wounds in her neck, which caused that swelling in her neck that you can see. The fluid built up so much that the choke chain she came in with was stuck around her neck, and we needed to call in next door's county animal control to use their bolt cutters and give her some relief," O'Reilly said.

The viral video, watched over 567,000 times since being shared on June 1, then shows Peanut Butter lying quietly with a devastatingly sad expression in her kennel, safe but alone, and not reacting to an outreached hand.

"She would cower in the corner of her kennel and, when the door would open, she went into survival mode and shook while avoiding eye contact," O'Reilly said.

Peanut Butter wasn't interested in treats and was stressed out by all the noise and commotion of the shelter. O'Reilly worried about it turning her "into a dog she so obviously wasn't."

Each year, around 6.3 million animals are taken into shelters across the United States, including 3.1 million dogs.

While the number appears huge, it is far decreased from 2011, where around 7.2 million animals, including 3.9 million dogs, wound up in shelters. And in further positive news, around 4.1 million shelter animals are adopted each year, including 2 million dogs, according to the American Society for the Prevention of Cruelty to Animals (ASPCA).

O'Reilly made the decision to take Peanut Butter home as a foster, and the change in her is immediate: the video shows her become an adored pet, getting cuddles, laying in a soft bed with a smile on her face, playing and cuddling.

Taking care to introduce Peanut Butter slowly, O'Reilly said she kept her separate from her other dogs for the first three days. And while she was first fearful of O'Reilly's partner, Jonathan, she eventually opened up to the "best foster dad".

"That first night's sleep is always my favorite part of bringing a foster home, and she took every bit of advantage of it," O'Reilly said. "She had the cutest snores from her little gargoyle snout, and I cried happy tears to see her so relaxed. I literally couldn't stop looking at her."

Plenty of commenters on O'Reilly's viral video of Peanut Butter urged her to adopt the dog permanently, but she said that, while those comments are "well-intentioned and sweet," she is an advocate for "the importance of fostering and for not pressuring fosters to keep their pets."

"An adopted home is one home for one pet; a foster home is one home for potentially an endless amount of pets who can be helped. And there truly feels like an endless amount of pets who need that help."

And this week, things worked out the way they were supposed to: while working at the shelter, a young couple with two small children and another dog at home met Peanut Butter and immediately fell in love with her.

"She was so gentle and sweet with their son," O'Reilly said. "He dumped the whole bag of treats on the cement, and she was immediately his biggest fan."

O'Reilly has been sent updates on how Peanut Butter is settling in at her forever home and she is "already enjoying her new life," she said.

"She loves their kids and she loves their other dogs, and while her kennel was very noticeably empty last night, our hearts are super full to have been part of her story," O'Reilly added.

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