Why does Meghan Markle have to curtsy to Kate Middleton? Bizarre royal rule explained

I don't know about you - but royal protocol is strange - I mean, why does Meghan Markle have to curtsy to Kate Middleton?

Most girls grow up wanting to be princesses. But while the tiaras are dazzling, it's apparent that being a royal isn't just a big game of dress-up - it's a job, just like any other.

Seriously, being a royal comes with a slew of stipulations that range from being inconvenient to downright bizarre. 

Why does Meghan Markle have to curtsy to Kate Middleton?

Although Meghan Markle is now officially the Duchess of Sussex - much like Kate Middleton is the Duchess of Cambridge through her marriage to Prince William - Meghan is still required to curtsy to her sister-in-law thanks to the royal family's hierarchical structure.

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According to protocol, Meghan is supposed to curtsy to those who outrank her. This includes the Queen, Prince Phillip, Prince Charles and his wife, Camilla. Because William is due to be the future King of England, he also receives a curtsy, and by extension so does Kate Middleton.

Are there any exceptions?

But this is where it gets weird. While Meghan is expected to curtsy to "blood princesses". That is, those who are born into the royal family, including Princess Anne, Princess Alexandra, Princess Beatrice, and Princess Eugenie - if she's with Prince Harry, the same blood princesses are required to curtsy to her because as a couple, she and Harry outrank them.

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Speaking to the MailOnline, an insider source explained: "A curtsy to Princess Anne? Yes. She’s the daughter of the Sovereign. Princesses Eugenie and Beatrice? Yes. But not if Harry’s in the room; then they should curtsy to her. Nor before Princess Anne’s daughter Zara Phillips, who despite being a blood royal will still be below Meghan in the pecking order (and expected to curtsy to her if Harry is present)."

What rules apply to Kate Middleton?

While Kate Middleton is destined to be Queen Consort, she also has to abide by some strange curtsying protocols. Of course, she has to curtsy to the Queen, Prince Phillip, Prince Charles and Camilla, but purportedly she's also obligated to bend the knee to "blood princesses", but this changes when William is present.

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"Without William, Kate would curtsy to Camilla; with him, she would not," the source continued. "That’s unless Prince Charles is present, in which case she would."

The order of curtsying, however, can change. This could happen when people marry into the family.

What about Meghan and Harry stepping back?

Now that Meghan and Harry have stepped down as senior royals, what rules still apply to them?

As etiquette expert, Myka Meier, explains to PEOPLE:

"It all is a bit murky. Now that they are keeping their HRH titles but not using them, the order of curtsy would stay the same as it has been since Meghan married into the family."

These rather complicated rules were drawn up by the Queen's private secretary, in a 2005 document referred to as the "Precedence Of The Royal Family To Be Observed At Court". This paperwork was apparently commissioned to "clarify Camilla’s position in the hierarchy following her marriage to Charles".

Well, there you have it. Being a royal isn't all fun and games, you see... There are complicated rules to stick by, and as it turns out, they're subject to change as well!