EXCLUSIVE: Kate Middleton Pregnant With Baby No. 3 — See How Pippa Middleton Reacted to the News!

Just a year and a half after welcoming her second child, Kate Middleton is pregnant with baby No. 3 — but not everyone in her family is happy about it!

A source tells Life & Style that the Duchess' younger sister Pippa Middleton is worried the news will "overshadow" her upcoming wedding to hedge fund manager James Matthews.

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"Pippa desperately wants the focus to be on her rather than her sister's bump," the insider shares.

(Photo Credit: Getty Images)

She's even thought about rescheduling her big day because of it. "Pippa is planning things around Kate," the source adds.

For more on the pregnancy, pick up the latest issue of Life & Style, on newsstands now! And scroll through the gallery below for a look back at Kate's best royal family moments.