Jenny from the blue-blooded block: Duchess of Cambridge dress designer Packham is inducted into the fashion royal family

Appearance of blue polka-dots on the new mother follows the likes of Helen Mirren and Judy Murray stepping out in Packham's creations

And so a member of fashion royalty is born: British designer Jenny Packham is now Jenny from the blue-blooded block. The Central Saint Martins graduate, who started out with her own bridalwear label in 1988, is this weekend seeing her latest creation spread across the cover of every glossy supplement.

In fact, you may have already seen it: blue, crêpe de chine, cornflower-blue, polka-dots. The dress in question was that worn by the Duchess of Cambridge as she presented George Alexander Louis to the world.

The consequences will not be short-term, but they were immediate: the Jenny Packham website crashing on Monday due to traffic overload. The dress respectfully acknowledges the absence of the young prince’s paternal grandmother, who also wore a blue hue and polka-dots leaving the hospital after the birth of William.

It goes beyond the Windsors. Dame Helen Mirren recently finished at the Gielgud Theatre where she played the Queen in An Audience. This, combined with her award winning performance in The Queen certainly makes her closer to royalty than the rest of us. The Dame was fashionably on point at the European premiere of her new action movie RED 2 on Monday in Leicester Square where she was wearing a scarlet Jenny Packham jewelled dress tastefully paired with nude pumps and clutch.  Oozing glamour and sophistication, the Dame (almost) always gets it right.

Mother of sporting royalty Judy Murray has also been wooed by the alluring glitz of Jenny Packham. Appearing at the winners ball after Wimbledon in a floor length sequin gown. A 31-year-old duchess, a 53-year-old sports coach, a 67-year-old actress Packham is nothing if not versatile.