14/08/2014 16:44 BST | Updated 20/05/2015 10:12 BST

Is Pippa Middleton's Social Life Being Controlled By The Palace?

Life as the Duchess of Cambridge's younger sister isn't as rosy as we all might think. In fact, being the sibling of a royal can impact who you're dating and which parties you can attend. Don't believe us? Just ask Pippa Middleton who's currently experiencing the annoying side of having a royal big sister.

Vanity Fair reports Pippa and her brother James were due to make an appearance at a VIP party in London last week to celebrate recently launched online boutique Cavan.

The bash was thrown by Cavan's ambassador Donna Air, who also happens to be James' girlfriend. So, did the Middletons show? Er, no. They skipped it - and it wasn't because they had a better offer.

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"Donna had invited James and Pippa, but neither of them came. It was odd because we were told they would be coming," a source told the magazine.

Fashion & Style reports James was worried his and Pippa's attendance might make Donna seem like she was using her "semi-royal connections for publicity."

However, there's also suggestions their mother Carole Middleton and even the palace might be involved.

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"The pair have been stepping out for a year, but sources close to the Middletons say that matriarch Carole Middleton keeps Air at arms length," says Vanity Fair.

Pippa also faced problems from "royal handlers" when launching her entertaining guide, Celebrate. Sources said the publishing process was made a "nightmare" by their interference.

It doesn't sound like we'll be seeing much of Pippa and James on the party circuit for a while then. Although, when have the young royals and their friends ever done what they're told?

LOVE PIPPA'S STYLE? See more of the near-royal below: