The four practical items the Duchess of Cambridge always carries in her handbag

The female members of the royal family are well known for their impressive collection of handbags - often carrying a different one every time they head out on an official engagement.

While the Queen famously favours her much-loved Launer handbags, Meghan Markle usually opts for a chic and sophisticated smaller handbag.

The Duchess of Cambridge is most often seen with an elegant clutch bag, although recently, she's taken a leaf out of her sister-in-law Meghan's book, with some bigger, more fashion-forward handbags.

And while there has been speculation about what the Queen carries in her everyday bag, there's always been some mystery surrounding the contents of Catherine's handbags when she's out and about.

MORE: The secret signals the Queen sends her staff with her handbag

But in a new book, Kate: A Biography, author Marcia Moody has revealed the four things that the Duchess reportedly always carries with her - and they might surprise you.

To stop her lips from getting chapped and dry, Catherine apparently always carries a lip balm. It's not clear which brand the Duchess favours, but we'd say this is a pretty solid handbag essential.

Next up is a handkerchief, which could come in handy on a few ocassions, be it an emotional engagement, or a day when she's simply feeling a bit under the weather.

Perhaps one of the most practical items on her handbag list is a compact mirror. Given that the Duchess of Cambridge is snapped by multiple photographers wherever she goes, we're not surprised by this one. We're sure that, like most of us, Catherine has a final glance at her reflection before stepping out of her car...

Finally, perhaps the most unusual item in the royal's handbag is some blotting paper. While it might not be something we'd carry in our bag, it makes sense for the much-photographed Duchess, to ensure her face is ready for the awaiting cameras.

Eagle-eyed fans will notice that the contents of Catherine's handbag don't include some items we'd probably all consider essential, such as a phone, keys or a purse. But, being the Duchess of Cambridge, it's probably unlikely she'll need to carry these things herself while on royal engagements - and let's face it, it's highly unlikely that she'd need to be making calls when she's on official business!

But in the past, her sister-in-law, Meghan Markle has actually been spotted carrying her phone with her, when she was on her official tour of Australia with Prince Harry.

And of course, these items appear to make up the inside of Catherine's official work bag, rather than the handbag she'd carry around during her time off, or during family time.

It's likely that the mum-of-three carries many more items with her when she's popping to the shops, or out with Prince George, Princess Charlotte, and Prince Louis.