The Queen gave a sweet subtle nod to Prince Philip in her birthday portrait

The Queen celebrated her 96th birthday this week, reportedly heading to Norfolk to spend the day at Sandringham in the late Duke of Edinburgh's favourite farmhouse on the property.

Not only were there events across the capital to celebrate the day - including gun salutes in Hyde Park and at the Tower of London - but the monarch also got her very own limited edition Barbie doll which is already proving so popular that it's selling out.

Prince William and Kate Middleton sent well wishes online, sharing an adorable personal photo of the Queen and her late husband with some of their great grandchildren, and the official Royal Family account also shared a sweet picture of Her Majesty when she was just two years old.

The Palace also released an official portrait of Queen Elizabeth II, taken at Windsor last month, with the monarch smiling and standing between two of her ponies, Bybeck Katie and Bybeck Nightingale.

However, many missed a small detail in the picture - and it is actually said to be a sweet nod to Prince Philip who sadly passed away in April 2021.

Wearing a dark green coat, the subtle tribute is said to be in remembrance of her husband. Many will remember that she also wore a similar shade to his memorial service last month, with the Royal website stating that his 'official' colour is dark green, explaining: 'The Duke of Edinburgh's official livery colour is dark green, known as 'Edinburgh Green'.

'It has been used for staff liveries - the Duke of Edinburgh's page at the Coronation wore dark green and silver - and private cars.'

The colour is also thought to recognise his service as an officer in Britain's Royal Navy during World War II.