Duchess of Cornwall admits to burying her sister's teddy bear in Hampshire garden near Alton

Camilla was followed for a behind-the-scenes ITV programme, Camilla’s Country Life, while she guest edited Country Life magazine to mark her 75th birthday.

The documentary-makers accompanied the duchess and her sister Annabel Elliot as they returned together to Hall Place near Alton, previously the Hampshire home of their grandparents.

Camilla, who married in 2005, buried her younger sister’s beloved teddy bear, known as ‘Tiddy Bar’, in the grounds and only confessed many years later.

Speaking in the documentary, the duchess said: ‘Yes, Tiddy Bar, he had a very happy resting ground.

Annabel said she had not forgiven her sister and that her toy’s disappearance ‘still rankles to this day’.

The pair recall rolling down the hills, catching butterflies in jars, and dressing correctly for their strict grandmother, as they chat about which of the furnishings they each now have in their own homes.

Camilla added: ‘I could find my way around here with my eyes shut.’

The hour-long insight, made by Spun Gold TV and award-winning director Michael Waldman, shows the duchess inspecting the final proofs of the special edition and carrying out her royal duties around the UK.

On guest editing Country Life magazine, the duchess said it was ‘quite hard work’ but she was ‘loving’ it.

Commenting on the challenges of personally penning an article about the Prince of Wales for the magazine, she said: ‘;It’s not easy to write about your husband.

‘I bit through several pencils.’

Camilla commissioned the Duchess of Cambridge to take her photograph for the front cover.

Kate, a keen amateur photographer, captured a smiling Camilla looking relaxed in a blue and white floral dress and cardigan, sitting on a bench with a trug filled with pelargoniums, ready to be planted.

Country Life edited by Camilla will be published on July 13, and Camilla’s Country Life documentary will be shown the same day at 9pm on ITV.

The duchess celebrates her 75th birthday on July 17.