We pored over thousands of pictures, and probed her favourite designers to find her favourite neckline, sleeve length and silhouette, the secret of that dazzling smile, the hidden value of her "down-to-earth" glamour - and just how she might adapt her McQueen as maternity wear.
"Both she and William share a genius from coming across as down-to-earth -with just enough glamour for them not to look like the Dutch royals," writes Armstrong. "It's the same knack that enables Kate to wear a high-fashion dress from Jonathan Saunders or McQueen, with her beloved courts and make millions of other women feel they could wear it too."
Harrods: Royal Engagement Wrap Dress. The Duchess of Cambridge's iconic engagement dress by Issa. Crafted from pure silk, the wrap over panels at the waist will provide a truly flattering fit. Pair with court shoes by day and strappy sandals by night. UK sizing Model wears a UK size 8 Pacific blue wrap dress Long sleeves Deep V-neck Wrap over panels at waist Concealed side zip fastening Pure silk Dry clean
British Vogue goes on sale on Wednesday, January 9th. For all this - and her role in the stratospheric increase in sales of sheer tights - see our February issue, on sale nationwide from Wednesday January 9.
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