The smart reason we don't see Kate Middleton break this royal beauty rule, according to an expert

The royal beauty rule that we don't see Kate Middleton break has been pointed out by a beauty expert and now we can't stop noticing. 

There are many rules that members of the royal family must follow when they're out in public - for example, clothes must remain modest, which explains why Kate Middleton is often seen wearing styles like powerful pantsuits and floor-length dresses and skirt. 

These strict rules also apply to their royals' beauty and makeup application. In fact, professional makeup artist Saffron Hughes just gave us a comprehensive list of the rules that women in the royal family are not allowed to break - and one particular rule is one we don't tend to see Kate stray from. 

Kate has, of course, perfected her beauty routine, according to Saffron.

Speaking on behalf of FalseEyelashes.co.uk, she explained, "From dress codes to etiquette rules, the royal family are mindful of the high standards that have been set for them. The Princess of Wales has perfected her execution of approaching beauty, even when following The Firm’s set rules and regulations," they said. 

One of the biggest beauty rules is that members of the royal family must never wear bright lipstick. As we know, Kate loves her subtly chic Clarins Ultimate Lip Perfector, which is the perfect hybrid of a gloss and a balm - but we don't really see her wear shades that range outside of her typical neutral pinks - and for a smart reason. 

"Bright lipstick can easily lead to a wardrobe malfunction, such as transferring to clothes, your teeth or even just looking two harsh against the skin," Saffron noted. 

However, while Kate tends to follow this rule closely, other more senior royals tend not to, said Saffron, "The late Queen Elizabeth had her own signature bright pink lip created so she could still enjoy a bright lipstick. Princess Anne often sports a bold red lipstick - sometimes even at royal events - throwing the royal rule book out altogether."

Another royal beauty rule that Saffron noted should never be broken is that heavy eye makeup is a pretty strict no-no in the family.

"Kate does like to sport a smokey eye for glamorous events but for royal and day to day affairs, her eye makeup remains bright and natural," they said of Kate. "Heavy eye makeup has a habit of straying underneath the eyes throughout the day, meaning wearing it at royal meetings wouldn’t picture well."

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