She was away from them for more than three years, but it took Cassie only a few seconds to recognize her long-lost family.

“It’s the Cassie dog!” exclaimed a tearful Brandy Metcalf as she bent down to let the 11-year-old Border Collie mix come to her. As the dog realized who she was, Metcalf said, “This is the best day of our lives!” (You can see their emotional reunion in the video below.)

When Metcalf and her husband, who live in Wake Forest, N.C., were expecting their third child, they sent Cassie to live temporarily with Metcalf’s sister in Charlotte, reported ABC News.

“We live in a small three bedroom, so it was close quarters with baby stuff. We were just trying to give the newborn the attention she needs,” Metcalf told ABC News.

Months later, when the family went to visit Cassie in Charlotte, Metcalf’s sister broke the sad news: The dog had run off one day when she was startled by a loud noise, and was still missing. The Metcalfs searched for her, but had no luck.

So Brandy Metcalf was in disbelief when she got a call on Sept. 11 that Cassie had been found, after more than three years away from her family.

“We gave scars and descriptions to confirm it was really her,” Metcalf said.

A Joyous Reunion

Cassie had lost seven pounds and was covered in fleas when Cheryl and Scott Smith of Charlotte found her, but they could tell the dog had once belonged to a family. A trip to the vet eventually revealed a microchip that had migrated around in Cassie’s body, although the information on it was outdated. Still, the Smiths managed to track down the elated Metcalf family.

When Cheryl Smith called the Metcalf home, “the wife, Brandy, could not even speak, she was in tears,” Smith told local TV station WBTV.

“We didn’t hesitate, we were on the road the next day,” Metcalf said.

“I only wish I could kind of see it through [Cassie's] eyes, to kind of know what she experienced and everything,” said David Metcalf. “It reminds me of a Disney movie.”

In this real-life adventure tale, the Metcalf family is extremely grateful to the Smiths for giving them their happy ending.