Four Yazidi refugee children have been reunited with their families in Calgary on Christmas Eve, after spending more than four years in ISIS captivity in Iraq.

Bindu Narula, with the Calgary Catholic Immigration Society, was at the Calgary airport to witness the tear-filled reunion on Tuesday.

"It's a perfect time of year for them to arrive so their families can spend some good time with them over the holidays and then we can start working solely on their integration," she said.

But, she said, it's also bittersweet.

"There's so much happiness. There's also the feeling of every time somebody comes … you remember everybody who doesn't come."

Bindu Narula, with the Calgary Catholic Immigration Society, said there were plenty of tears and emotions during Tuesday's reunion. (Hala Ghonaim/CBC)

The Yazidis are a religious minority with a 6,000-year-old culture based mainly in northern Iraq. ISIS launched brutal attacks targeting the Yazidi community in August 2014.

The United Nations has recognized the atrocities by militants against members of the religious minority as a genocide. Thousands of people were killed and enslaved, and hundreds of thousands displaced.

The four boys who arrived Tuesday are between the ages of 11 and 16.

"Short term, they're going to go home, they're going to sleep, eat mom's cooking," Narula said.

Since 2017, 292 Yazidi families have resettled in Calgary and more than 1,400 across Canada.

Fariborz Birjandian, the Calgary Catholic Immigration Society's CEO, said despite the horrors that the families have seen and experienced, many have flourished since arriving in Canada.

"When you compared to the state they were in when they arrived, they are doing amazingly well. I mean it just shows how resilient they are," he said.