The astonished teenager, who was due to spend a week with her friend and her friend's grandparents in a villa near Albufiera, had made it all the way to the gate before anyone raised the issue of Portugal's stricter guidelines to her.
Eilidh said: "I went to the gate when boarding was called, but when I got to the desk the woman took me out of the queue and said I could not fly as I didn't have a letter giving my parents' consent and saying who was picking me up at the other end.
"It was really embarrassing."
Eilidh and her parents had believed she would be alright to fly by herself as the Jet2 website saying it "allows persons aged 14 or over to travel alone".
The website fails to make clear that Portugal put stricter requirements in place in the wake of the Madeleine McCann case, which meant 16-year-old Eilidh was still considered a minor and couldn't fly without a letter of consent from her parents, as well as details of who would collect her at Faro.
- Daily Mail