Rita, the couple's dog, was a 4-month-old English bulldog that died last year. Her owners say they took Rita to PetSmart in Downey to be groomed.
Shortly after dropping Rita off, they got a call that she was vomiting blood and that they needed pick her up and take her to a vet. After doing so, Rita died 45 minutes later.
According to the lawsuit, a necropsy found that Rita died of strangulation. The couple is seeking unspecified damages in the lawsuit.
PetSmart told ABC7 in a statement: "We take very seriously the trust placed in us by pet parents who each day leave their pets in our care. Nothing is more important than looking after the safety and well-being of pets. The facts as represented in the recently distributed press release by an attorney are not what we believe to be true relative to this unfortunate situation."