But the story doesn't end there.
Diana Ratsamee learned during that horrible ordeal what it's like to lose a best friend.
"Someone that will always be there for you, who you look forward to seeing when you come home, and someone who looks forward to seeing you when you get home," she says.
Diana told the KOMO News Problem Solvers about her quest to find the man whose dog killed Champ in Foster Memorial Park last Sunday when she took the little chihuahua for a walk there.
Champ was one of Diana's best friends. The little chihuahua was also a best friend to Diana's young niece, Melina Quach, who was walking Champ when he was killed.
"The guy kept saying, 'Your dog is dead. Your dog is dead.' I think he said it three times. And when the other dog let go, he just walked away and just left me," says Melina.
Champ died on the way to the veterinarian. But thanks to the help of a stranger, that's not where the story ends.
Eric Bertlesen read Champ's story on KOMO News and contacted the Problem Solvers.
His dogs, Pepper and Pedro, just had a litter of five - and little Bleach was looking for a home.
Eric knows that Bleach, who is half chihuahua, can't replace Champ - but he says handing her over sends a message of hope.
"I just wanted a little girl not to think all people are bad," he says. "So you just have to do as much good as you can to offset the evil."
He saw it as a chance to honor one best friend through the life of another.
"It's good to have my faith in humanity restored," says Diana.
Diana told KOMO News she felt disappointed the other dog owner didn't take responsibility when Champ was killed. But she says - this new dog helps heal those wounds.