Question: Who was maid of honour at her sister, Duchess of Cambridge, wedding to Prince William?

full_context: Document 1: Urban Outfitters: Urban Outfitters, Inc. is an American multinational clothing corporation headquartered in Philadelphia, Pennsylvania. It operates in the United States, Belgium, Canada, Denmark, France, Germany, Italy, Ireland, the Netherlands, Pakistan, Sweden, United Kingdom,Spain and Israel (soon). Its inventory primarily consists of women's and men's fashion apparel, footwear, beauty and accessories, activewear and gear, and housewares, which largely draw from bohemian, hipster, ironically humorous, kitschy, retro, and vintage styles. Their targeted group is young adults aged 18 to 28. The company has additionally collaborated with designers and luxury brands on several occasions. Urban Outfitters manages five separate brands, including its namesake, Anthropologie, Free People, Terrain, and BHLDN; together, the brands operate over 400 retail locations worldwide. Today, it sells its product to approximately 1,400 specialty stores and select department stores. Other than that, merchandise is sold directly to customers through websites, mobile applications, catalogs and customer contact centers. As of January 31, 2015, total of 238 Urban Outfitters stores are operating, in which 179 are located in the United States, 16 are located in Canada and 43 are located in Europe.
Document 2: Camilla, Duchess of Cornwall: Camilla, Duchess of Cornwall, ("née" Camilla Rosemary Shand, previously Parker Bowles; born 17 July 1947), is the second wife of Charles, Prince of Wales, the eldest child and heir apparent of Queen Elizabeth II. Instead of using the title of Princess of Wales, she uses the title Duchess of Cornwall, her husband's secondary designation. In Scotland, she is known as the Duchess of Rothesay. In the event of Charles acceding to the throne, Camilla would become a queen consort; however, an official statement issued by Clarence House on the day of her marriage to Charles announced that she would be known as the Princess Consort.
Document 3: British Boot Company: The British Boot Company (formerly known as Holts) is a shoe shop in Camden Town in London notable for being a leading UK stockist of English brands such as Dr Martens, Grinders, Solovair, Gladiator, George Cox, Tredair and NPS.
Document 4: Princess Charlotte of Cambridge: Princess Charlotte of Cambridge (Charlotte Elizabeth Diana; born 2 May 2015) is the younger child and only daughter of Prince William, Duke of Cambridge, and Catherine, Duchess of Cambridge. She is fourth in line of succession to the British throne, after her paternal grandfather, her father, and her elder brother.
Document 5: Catherine, Duchess of Cambridge: Catherine, Duchess of Cambridge (Catherine Elizabeth "Kate"; "née" Middleton; born 9 January 1982) is the wife of Prince William, Duke of Cambridge. Following his father Charles, Prince of Wales, William is second in line to succeed his grandmother, Queen Elizabeth II, as monarch of the United Kingdom and 15 other Commonwealth realms, making Catherine a likely future queen consort.
Document 6: Hobbs Ltd: Hobbs is a women’s clothing, footwear and accessories retailer based in London, UK. It was founded in Hampstead in 1981 and began as a shoe retailer. Hobbs now has stores across the United Kingdom and concession stores in the United States and Germany. The online store serves 55 countries worldwide. Hobbs is popularly associated with clothing priced in the mid range for a customer base that is largely middle-aged and older. Among its best-known customers are the Duchess of Cambridge and her sister, Pippa Middleton.
Document 7: Brent Hoberman: Brent Shawzin Hoberman CBE (born 25 November 1968) is a British entrepreneur. Together with Martha Lane Fox, he founded Lastminute.com in 1998, an online travel and gift business. As CEO, Hoberman successively floated and later sold Lastminute.com Ltd to Sabre who purchased the company’s equity and bond debt for £577 million (including additional gross debt of approximately £79 million and estimated cash at bank in hand of approximately £72 million). In 2006, Hoberman handed over the CEO position to Ian McCaig, although he remained as chairman and chief strategic officer until 2007.
Document 8: Kate Middleton effect: The Kate Middleton effect (also the Kate effect, the Duchess of Cambridge effect or the Duchess effect) is the trend effect that Catherine, Duchess of Cambridge, is reported to have had on others, for example in sales of coral-coloured jeans. Although Middleton was in the public eye for many years as the girlfriend of Prince William, the effect began after the announcement of the couple's engagement in November 2010, which spawned a media frenzy.
Document 9: Princess Beatrice of York: Princess Beatrice of York (Beatrice Elizabeth Mary; born 8 August 1988) is the elder daughter of Prince Andrew, Duke of York, and Sarah, Duchess of York. Prior to the birth of Princess Charlotte in 2015, Beatrice was the highest ranking female in the line of succession, and is now seventh in line of succession to the British throne.
Document 10: Talbots: Talbots is an American specialty retailer and direct marketer of women's clothing, shoes and fashion accessories.
Document 11: James William Middleton: James William Middleton (born 15 April 1987) is an English businessman and member of the Middleton family. Middleton's companies include Boomf. He is the younger brother of Catherine, Duchess of Cambridge, and read the lesson at her wedding to Prince William, Duke of Cambridge.
Document 12: Wedding of Prince William and Catherine Middleton: The wedding of Prince William, Duke of Cambridge, and Catherine Middleton took place on 29 April 2011 at Westminster Abbey in London, United Kingdom. The groom, Prince William, Duke of Cambridge, is the eldest son of Charles, Prince of Wales and Diana, Princess of Wales, and second, after his father, in line to succeed his paternal grandmother, Queen Elizabeth II.
Document 13: Debenhams: Debenhams plc is a British multinational retailer operating under a department store format in the United Kingdom and Ireland with franchise stores in other countries. The company was founded in the eighteenth century as a single store in London and has now grown to 178 locations across the UK, Ireland and Denmark. It sells a range of clothing, household items and furniture and has been known since 1993 for its 'Designers at Debenhams' brand range.
Document 14: Made.com: MADE.COM is a brand based in London, England that designs and retails homewares and furniture online, and across a network of experiential showrooms in Europe. The company was co-founded by Ning Li (chief executive officer) and Brent Hoberman (Chairman and founder of Lastminute.com), together with Julien Callède (Chief Operations Officer) and Chloe Macintosh.
Document 15: Pippa Middleton: Philippa Charlotte Middleton ( ; born 6 September 1983) is an English socialite, author, columnist, and the younger sister of Catherine, Duchess of Cambridge. Middleton began receiving media attention with her appearance as the maid of honour at her sister's wedding to Prince William. After marrying James Matthews in 2017, she will be styled Lady Glen Affric should he inherit his father's title.
ground_truth: Pippa Middleton