Details of Prince Philip and his private life are somewhat lesser-known than other members of the British Royal Family. This may be due to the fact that the late husband of Queen Elizabeth II served in a support role to the monarch.

But the Duke of Edinburgh had an eventful past—one that's been shaped by numerous strokes of fate, including the early death of his older sister Cecilie.

Prince Philip's Sister Cecilie Died in a Plane Crash

Prince Philip grew up with four older sisters

In 1921, Philip was born as a Prince of Greece and Denmark in Corfu and grew up with four older sisters. The family had to flee Greece after a military coup in 1922. Philip went to Paris with his mother and sisters, while his father left the family for another woman.

After the Nazi Party rose to power, Philip was sent to the Gordonstoun boarding school in Scotland. In 1931, his older sister Cecilie married the German nobleman Georg Donatus von Hessen-Darmstadt and moved with him to Germany. The couple had two sons, Ludwig and Alexander, and daughter Johanna. They also joined the Nazi Party in May 1937, a few months before they died.

Cecilie's family was on their way to London

On Nov. 16, 1937, the fateful flight took place. The family was flying to the wedding of Cecilie's brother-in-law Ludwig and his future wife Margaret Campell Geddes, which was to take place the next day.

There were 11 people on board the plane — Cecilie, who was heavily pregnant with her fourth child at the time, her husband, two sons, Georg Donatus' mother-in-law, a nanny, two friends, and three crew members. Only Johanna, the youngest of the family, had to stay at home at Wolfsgarten Castle with a nanny because she was too small for the trip.

After the start in Frankfurt, a stopover in Brussels was planned, but due to dense fog, the plane had to be diverted to the city of Ostend, on the North Sea coast. But there, too, visibility was poor. Nevertheless, the pilot decided to land — a fatal mistake.

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Prince Philip's sister Cecilie died in the plane crash

The plane hit the chimney of a brick factory in Ostend, crashed into the hall below and went up in flames. All 11 passengers and crew died in the plane crash.

When investigating the wreck, employees also found the remains of a male infant. Several theories came out at the time, suggesting Cecilie had given birth mid-flight and that the labour may have motivated the abrupt landing. However, this can no longer be proven today. When Prince Philip heard of the tragic event, he was just 16 years old. 

Prince Philip

He never spoke publicly about the loss. The plane crash was also covered in the episode "Paterfamilias" of Netflix's The Crown. Philip remembers his time at the Scottish boarding school where he learned of the death of his sister, later having a traumatic experience at her Nazi funeral.

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