Pippa Middleton was positively glowing in a tailored plum dress at a Spectator party at Belgraves Hotel in London, on Tuesday night. The 31-year-old, who is a regular columnist for the weekly cultural and political magazine appeared relaxed and happy at the event. And just weeks away from the birth of a new niece or nephew, she looked demure in the purple number by with a coral belt and matching high heels, which served to showcase her slim physique. Scroll down for video . Plum dream: Pippa looked happy and relaxed in the purple dress at Spectator Life's third birthday party at Belgraves Hotel in London . Pippa's plum pencil dress . Click to shop Tabitha Webb's current collection! Visit site . We do love to see Kate and Pippa out and about. We've been treated this past week to many royal engagements, which means a lot of spying on Kate's maternity fashion. And now it's all been topped off with an appearance by Pippa at a party in London. We are so spoilt! Pippa stunned in a simple pencil dress by one of her favorite designers, Tabitha Webb. The cute plum number suited Pippa's tanned skin to a tee and she topped it all off with a studded clutch by Hoss Intropia, which brought out the color of both her ribbon waistband and pointed courts. Sadly, neither the dress or the bag are up for grabs, but if you click to the right, you'll head to Tabitha Webb's website where you can shop the current collection. The brand hasn't been around long. It launched its first bespoke collection in 2013 with its aim to make English elegance accessible. And it's a job well done as she's now gained a huge celebrity following. If you're loving Pippa's plum style, see our edit of exciting options in this rare hue below. Cameo Play with Fire Strapless Dress at NastyGal (Now $117.60) Visit site . KAMALIKULTURE by Norma Kamali Sleeveless Shirred Waist Dress . Visit site . Badgley Mischka Collection Neck-Twist Day Dress at Neiman Marcus (Now $198) Visit site . Halston Heritage Side-Twist Pleated Dress at Neiman Marcus (Now $225) Visit site . The flattering knee-length frock by Tabitha Webb had stylish cap sleeves and featured boxy pockets - and she kept her legs bare, all the better to show off her tan. She completed the sophisticated look with subtle accessories including a small embossed box clutch from Hoss Intropia, a gold watch, simple gold chain necklace and earrings. The brunette, who wore her hair in loose, glossy curls, even kept her make-up subtle. The Spectator was first launched in 1828, making it the oldest published magazine in the English language. Spectator Life is the lifestyle supplement from the main magazine and the Duchess of Cambridge's sister has contributed columns about food, truffle hunting and wine tasting since December 2012. Pippa joined other celebrity guests to celebrate the supplement's third birthday at the swanky Belgravia venue. The Duchess of Cambridge's sister (pictured right) was seen in company of Andrew Neil (pictured left) who is the Chairman of the Press Holdings Group - which owns The Spectator . Familiar faces at the bash included  Guy Pelly, an old school friend of Princes William and Harry, who is also godfather to her nephew Prince George. The nightclub owner was escorted by his wife Elizabeth, who teamed her crisp white shirt with an acid lemon skirt. Pippa talked and posed for pictures with Andrew Neil, the Chairman of the media group that owns The Spectator. The brunette matched her accessories accordingly with her belt and clutch bag all in a similar nude shade . Royal BFF: Guy Pelly (pictured right) is close friends with the Duke of Cambridge and Prince Harry, and attended the party with wife, Elizabeth Pelly . This is only Pippa's second outing since returning from the US where she was in talks with the NBC network about a presenting role. A keen sportswoman, who's currently in training for the 50-mile London to Brighton Bike Ride, she recently stunned in an ice-blue floor length gown at the Disability SnowSport UK Ball. She met Heather Mills McCartney at the event and gave a speech in which she called for there to be more winter sports opportunities for disabled athletes. Windswept in plum! Pippa was all smiles as she entered Belgraves hotel for the party, wearing a mulberry wrap coat over her Tabitha Webb frock .
The Duchess of Cambridge's sister attended the party at Belgraves Hotel . She wore a Tabitha Webb dress and Hoss Intropia clutch . The 31-year-old is a columnist for main magazine, The Spectator . TOWIE's Lucy Mecklenburgh and royal chum Guy Pelly also attended .