Duchess of Sussex with Prince Harry. (Pic: Instagram)

Perhaps she was keen not to upstage the bride – after all, it’s only four weeks since the entire world watched her own wedding.

Which may explain the Duchess of Sussex’s choice of outfit when she and Prince Harry watched his cousin marry on Saturday.

The floaty £3,922 (about R70 000) blue and white wrap dress was from Oscar de la Renta’s 2019 collection, which is not on sale yet but is available to order for delivery next year.

She teamed it with a white fascinator and high white heels which saw her almost slip over as she walked through the grassy churchyard. Luckily she had a firm hold of Harry’s hand and managed to stay on her feet.

The dress received mixed reviews among royal watchers, with some likening it to a baggy dressing gown or a pair of curtains.

For Harper’s Bazaar, however, it was the ‘perfect outfit for the summer nuptials’.

Another guest catching the eye was Earl Spencer’s daughter Lady Kitty Spencer, 27, a model. She wore a £3,850 (about R70 000)  peony-print chiffon dress with a pie-crust collar from Dolce & Gabbana’s pre-fall range. She added a diamante belt and a berry-coloured hat by milliner Philip Treacy, with purple trim and a birdcage veil, teamed with jewellery by Bulgari for which she is a brand ambassador.

The occasion was the marriage of Celia McCorquodale, younger daughter of Princess Diana’s sister Lady Sarah McCorquodale.

The bride wore the tiara that Diana wore for her wedding to Prince Charles in 1981 as she married George Woodhouse at St Andrew and St Mary’s church in Stoke Rochford, Lincolnshire.

She was among a number of members of Diana’s family who attended Harry and Meghan’s wedding last month after he expressed his wish to involve his mother’s side, and she returned the favour by inviting the duke and duchess to hers.

Also in attendance were Diana’s siblings Lady Jane Fellowes and Earl Spencer, along with his son Viscount Althorp and Lady Kitty. The bride, 29, arrived at the church in a vintage 1910 Rolls-Royce Silver Ghost. Her husband is a sales negotiator at Savills estate agents.

© Daily Mail