Mr McCullough had also woken up about 3.30am when he heard the side gate to their backyard open, where Pippin and their other dog Millie were.
He had a look around, went out to the street, and saw a man walking a dog, not realising Pippin was gone.
The family was over the moon to get her back.
"It's been hell for us the last few days," said Mr McCullough.
"I was crying I was so happy."
Mrs McCullough said their three boys were so excited when they got the call.
"They shot into the car, Tobey and Jude were still in their PJs."
She said Pippin was fine but seemed a little out of sorts.
The McCulloughs said they had been put under a lot of stress but they were just glad the man rang the pound.
"I'm more glad, I'm so relieved at the moment," said Mrs McCullough.
A Masterton District Council spokesman said Pippin arrived at the pound on New Year's Day and was scanned yesterday. No impound fee was charged.
The McCulloughs said they had asked the pound to keep a look out for a dog with a collar but as the collar had been taken off, she wasn't immediately identified.
A photo of Pippin put on the Times-Age Facebook page on New Year's Day reached more than 60,000 people and was shared 840 times.
The McCulloughs said they didn't know if the man who handed in Pippin had seen the post but they thanked all the people who shared it on social media.