The couple, from Hampshire, had been on a trip to Nice when little Olivia decided to make a dramatic entrance into the world - three months ahead of her due date.
Her parents had to find emergency accommodation so they could stay in the country while their tiny daughter was cared for in hospital.
The little girl weighed in at a respectable 3lbs 10oz given her prematurity, and will stay in France until she is deemed big enough to travel back to the UK.
Her proud - but somewhat shocked - grandad Steve Markham, 62, told the The Gloucester Citizen that Olivia is doing well but is still being closely monitored.
"They've had to register her birth in France so she will need a 48-hour British passport to be able to come home," he said. "She is okay but they are keeping a very close watch on her – it's one day at a time."
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