The London flat where Princess Diana was 'happiest' will be honoured with a blue plaque

She had a sign that said 'Chief Chick' above her door.

A frequent fixture in series 4 of The Crown, the West London flat where a young Diana, Princess of Wales, lived before marrying Prince Charles will be given its own English Heritage blue plaque.

Marking the year in which she would have celebrated her 60th birthday, English Heritage have announced they will be honouring Diana with a 'memorial tablet' – and though the location of the blue plaque is yet to be confirmed, it's thought that it will be placed at the Earl's Court flat where the princess is reported to have been 'happiest'.

The 'People's Princess' shared the flat with friends before she wed Prince Charles in 1981, and is said to have had a sign above her door saying 'Chief Chick'.

According to biographer Andrew Morton's book Diana, In Her Own Words, Diana described the years she lived in the three-bed flat as ‘the happiest time of her life’ – so it's only fitting that it's where the honorary plaque is likely to be placed.

Diana’s brother, Charles Spencer, appeared to confirm the location of the plaque on Twitter, writing, ‘How very lovely that this blue plaque will be going up outside Coleherne Court – thank you, @EnglishHeritage, for commemorating such a very happy place for Diana in this way.'

Diana was nominated to receive the honour by the London Assembly following a campaign asking Londoners to suggest women worthy of a blue plaque.

‘It was considered in the normal way and the panel felt it was a really good case. Diana is undeniably a really significant figure of the late 20th century,' said Anna Eavis, English Heritage’s curatorial director. 'She made a huge impact and was very popular.’

Diana's youngest son Prince Harry and wife Meghan Markle, Duchess of Sussex, are rumoured to be returning to London to mark her birthday on 1st July, which follows shortly after The Queen's platinum jubilee in June.

The couple stepped down from their royal roles earlier this year to begin a new life in California with one-year-old son Archie. But following rumours of a royal rift in the wake of their explosive Oprah interview, it's unclear whether Harry and Meghan will be returning back across the pond in the summer.