7 On Your Side: What to know before buying a pet

It was a Mother's day gift for the D'Souza family - toy dog chosen at a the local pet store. The kids picked the puppy out, but their excitement quickly turned to devastation in 48 hours.

As soon as the family named him 'Freddy,' they say their brand new 10-week-old puppy had problems. The Lhasa Apso Yorkie mix was lethargic and not eating after bringing him home, but the new owners thought it was normal.

"I just thought he was a quiet dog," said Kevin D'Souza.

By the second day, Freddy could barely move.

"By Tuesday he was throwing up and had some diarrhea," said Celine D'Souza.

She said she called the animal clinic for an appointment, monitored the dog overnight, and was about to bring him in to be examined the next day.

"That night we went to bed, in the morning he was no more he just died," Celine said.

Sadly, the puppy passed away. Celine's son and 9-year-old daughter were devastated.

"She keeps asking me 'why did Freddy have to die? What happened mommy? We just got him home,'" said Celine.

So what happened when Celine called the pet store where they had just bought the puppy on Mother's Day?

"He blamed us and said 'how would I know you did anything to the dog?' I'm like 'are you serious?'" said Celine.

The pet shop refused to refund her $1,300 purchase price. Celine said the pet shop owner requested she get an animal necropsy, but that would cost $800. More than the family could afford.

She wasn't familiar with New York law. To get a refund for a sick or dead pet, she only needed a vet letter stating the dog is "unfit for purchase."

Also, state law says before sale pet shops must get each dog examined by a vet. The health certificate is available upon request. Celine never asked for it. 7 on your Side asked for it, and within hours, instead of seeing the certificate, she was offered and then paid a refund.

The big takeaway is that before buying a dog, in New York, request to see the Health Certificate and make a copy of it. Next, if there's a breeder involved - research. First, see if he or she is licensed by the USDA. In this case, the breeder wasn't licensed, so Celine was buying blind.

If there is a problem with your pet purchase, it is important to familiarize yourself with the pet lemon law. It comes down to three words - "unfit for purchase." In order to get a refund you'll need a letter from a vet stating that.