Kate Middleton is known for her amazing wardrobe and will no doubt have a team of stylists and fashion experts who help her choose outfits.
According to a royal etiquette expert, the Princess of Wales follows a few very basic style rules which ensure that all her clothing is seamless with no underwear edges visible through her garments.
Myka Meier suggested that Kate's secret is wearing strapless and seamless underwear that gives her a flawlessly smooth finish, the Express reports.
Ms Meier who trained under a member of The Queen's Royal Household took to Instagram to upload a photograph of a nude-coloured strapless shapewear piece which she claims is Kate's secret fashion hack.
She captioned the post: "Royal Style Hack Alert. Ever wonder why you never see bra straps?!
"Swipe to see a secret trick which is a must-have royal wardrobe piece!”
Myka explained further: "Underwear and bras are also considered private intimate wear, and for royals to put intimate apparel on display would simply not be done."
According to the expert, "there are a few options" when it comes to hiding pesky bra straps and the shape of the cups with the obvious option being to wear strapless shapewear.
Another option is the bra being sewn into the item of clothing.
When it comes to visible pant lines in trousers, form-fitting dresses or light coloured clothing like white or cream it's best to wear seamless pants or longer shapewear to avoid underwear edges.
There are also a wide variety of underwear shades to suit any skin tone so they can appear transparent and won't be visible through clothing.
Myka advised that the right underwear is crucial so the "attention is on the beautifully tailored and designed garment and not the undergarments".
She added: “Undergarments showing can take away from an amazing outfit.”
The royal etiquette expert told Fabulous that bodysuits are often chosen by female royals when wearing a flowy skirt or dress as it protects their modesty and keeps everything neatly tucked in.
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