Travelling in a state Land Rover, the Queen appeared to be in high spirits as she travelled with her lady-in-waiting. The duo twinned in blue with both ladies opting to wear cornflower blue dresses. In a further display of camaraderie, Lady Susan echoed the Queen in her choice of jewellery, choosing to wear pearl earrings and a pearl necklace.
WATCH: The Queen's Jubilee celebrations day by day
The Queen was moreover spotted wearing orange-tinted sunglasses to shield her eyes from the sunshine.
Lady Susan, who was married to the late BBC chairman Marmaduke Hussey, has been a friend and loyal assistant of the Queen since she joined the court in 1960.
During the Covid pandemic, she formed part of the HMS Bubble and attended to the Queen at Windsor alongside 20 other key staff members.
Her lady-in-waiting played a vital role during the pandemic
She is the fifth and youngest daughter of the 12th Earl of Waldegrave and Mary Hermione, Countess Waldegrave. She is also godmother to the Duke of Cambridge and shares a close bond with the Prince of Wales.
A constant presence in royal life, Lady Susan has largely remained out of the spotlight, but was famously photographed in 2012 draping a pashmina over the Queen's shoulders as they sailed down the Thames in the pouring rain on the Royal Barge for the Jubilee pageant.
Their recent sighting comes amid Trooping the Colour which took place on Thursday in central London. For the first time ever, the Queen took the salute from the comfort of the Buckingham Palace balcony owing to ongoing mobility issues.
Lady Susan accompanied the Queen to Buckingham Palace
Earlier this morning, more than 1,500 officers and soldiers and 350 horses from the Household Division put on a regal display on Horse Guards Parade, with the colour trooped by the 1st Battalion, Irish Guards.
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