The story went viral online and was covered by numerous outlets including the Daily Mail and the Telegraph in the UK, Italy's La Repubblica, The Huffington Post and USA Today as well as a raft of pet and clickbait websites.
Ms Wills said the reach of the story had been "absolutely amazing", though said cats were not generally known for their strong maternal instincts. She said presumably, the cat was dumped along with her kittens but was able to escape from the box.
Read more: Mother cat reunited with her litter
Over the past month, a family member of one vet had fostered mother Gabby and her kittens - Tyron, Muffin, Benny and Dobby - who were now about eight weeks old and ready for new homes.
"We are auctioning them and giving the money to the SPCA, to help other not-so-lucky abandoned kittens," the clinic posted on Facebook.
Mill Road would give the kittens their first round of vaccinations and desex them for free when the time came. Gabby would stay permanently with her new foster family.
"We have made a separate post for each kitten, so if you have your heart set on one of our famous kittens, you can bid for the one you like," the clinic said online.
Ms Wells said it was relatively rare for people to dump pets at the clinic, with the SPCA bearing the brunt of abandonment. Whangarei SPCA manager Francine Shields said this year, the shelter "really hadn't stopped having kittens".
-Find "Mill Road Vet Clinic" on Facebook to bid on a kitten.