Kate Middleton's sister, Pippa Middleton, is not engaged to boyfriend Nico Jackson, despite reports that the couple have taken the next step after six months of dating Credit: Karwai Tang/WireImage.com

A Pippa Middleton wedding is not in the cards -- yet. Reports claim that Kate Middleton's younger sister is engaged to her boyfriend Nico Jackson, but a source tells Us Weekly that's simply not the case.

The party planner -- and her lower backside -- first made major headlines when she stunned in a tight-fitted Alexander McQueen dress while serving as maid of honor at the Duke and Duchess of Cambridge's nuptials in April 2011.

Middleton, 29, and stockbroker Jackson, 35, have been dating for more than six months. The two reportedly went together to meet her nephew, Prince George, at Kensington Palace shortly after his July 22 birth.

Middleton was previously linked to England cricketer Alex Loudon from 2010 to 2011 and dated university friend George Percy in 2012 for a brief time.