Grandparents from Cape Breton were put to the test earlier this week when they were driving their son and his pregnant girlfriend to the hospital — and the baby decided it was time to be born.

John "Tiny" Cremo and his wife Karen piled their 20-year-old son Gavin Cremo and his 19-year-old girlfriend Autumn Dennis-Doyle into their car on Wednesday and took off from Waycobah when Dennis-Doyle's contractions were 10 minutes apart.

As they drove toward the Cape Breton Regional Hospital in Sydney, Doyle's water broke. The family was still about a 20-minute drive away from the nearest hospital in Baddeck.

John Cremo pulled into a plowed parking lot of a former gas station and his wife called 911.

"I thought to myself, 'I've got to find a good spot to drive in and see what we can do, because I don't want to be parked beside the road,'" he said.

"911 told the wife what to do and my son was kind of panicking but it's all right — I understand. So I said, 'I'm going to take over."

Baby born

Gavin, Karen and John Cremo sit with baby Arabella Grace at the Cape Breton Regional Hospital on Thursday. (CBC)

Cremo, who happens to be the fire chief of the Waycobah Volunteer Fire Department, put on a pair of gloves and stepped in to help when the baby's head started to crown.

"I went in the truck and I said, 'OK, you got to lay down and we might as well deliver this baby I guess,'" he said.

Cremo said Dennis-Doyle pushed twice and the baby girl was born.

He tied the umbilical cord with his shoelace and an ambulance arrived from Baddeck minutes later and took mother and baby to hospital. The family is now at the Cape Breton Regional Hospital.

Cremo said as fire chief, he's used to handling emergencies. He said Dennis-Doyle was calm through the birth — this is the couple's second child.

Mother, father and eight-pound baby girl Arabella Grace are all doing fine, said Cremo.