Ryan and Evie Cordell, who live near Boston, said their daughters, Cadence, 12, and Emerson, 9, and their three young boys had been asking for a dog since their family dog of 10 years died in August, ABC News reported Thursday.
The Cordells said the girls read about a family who bought a new cat for their children when they received more than 10,000 likes for a Facebook picture, so they convinced their father to promise them a puppy if their page could top 1 million likes.
The girls took a picture of them holding a sign with their younger brothers and had their mother create a page for people to like.
"Hi World, We want a puppy. Our dad said we can get one if we get 1 million Likes! So LIKE this! He doesn't think we can do it!" the sign read.
The page received more than 1.2 million likes in less than 24 hours.
"I really don't know how it moved so quickly," Evie Cordell said. "We thought it'd top out at maybe 2,000 people."
She said the family is now looking for a puppy.
"We are looking at adoption through a rescue or a local shelter," she said. "I think we want a lab or a golden retriever, either a puppy or a very young dog so it can grow up with our family."