The Duke of Edinburgh visited Estonia earlier in January, where he met troops from The Royal Dragoon Guards who had been deployed on a training exercise.
The royal family's Instagram account shared several images from Prince Edward's trip, which showed him in combat uniform in his role as Colonel-in-Chief of the regiment.
While many fans praised the royal for his work, they also noticed a strong resemblance between Edward, 60, and one of his late relatives.
"He looks so much like George VI," one social media user commented.
"He looks so much like his Grandfather, George VI - it's quite remarkable," another agreed.
"He looks like his grandpa King George VI," a third added.
© Instagram @royalfamily/GettyThe late Queen's father George VI sadly died in 1952 – 12 years before his grandson Edward was born.
As well as sharing an incredible likeness, Edward seems to have inherited his late grandfather's love of tennis.
George VI competed in the Men's Doubles at Wimbledon in 1926, while Prince Edward developed a passion for real tennis while completing his Duke of Edinburgh Award.
© GettyWhile Edward dropped out of his military training with the Royal Marines in 1987, the Duke does wear uniform for ceremonial occasions.
He supports the work of the Armed Forces in the UK and overseas, and currently holds eight military appointments, including Royal Honorary Colonel of the Royal Wessex Yeomanry and The London Guards, and Royal Colonel of 2nd Battalion The Rifles.
© GettyHis grandfather, George VI, served in the Royal Navy and the Royal Air Force during the First World War.
The Duke and Duchess of Edinburgh's daughter, Lady Louise Windsor, 21, is training with the St Andrews' University Officers' Training Corps (UOTC).
© GettyThe young royal, who is studying English at St Andrews, is said to be keen to become the first female royal to serve in the military since her late grandmother, Queen Elizabeth II.
It comes after Lady Louise reportedly stated on her LinkedIn page: "I am interested in pursuing a career in the military, diplomacy, or law."
