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

Context articles: Kate Middleton effect
Louisa Hamilton, Duchess of Abercorn
Duchess of Cambridge
Hobbs Ltd
2011 royal tour of Canada
James William Middleton
Wedding of Prince William and Catherine Middleton
Amanda Pullinger
Pippa Middleton
Baron Carrickfergus

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.
Louisa Jane Hamilton, Duchess of Abercorn, VA (née Lady Louisa Jane Russell) (8 July 1812 – 31 March 1905) was the wife of James Hamilton, 1st Duke of Abercorn, and the daughter of John Russell, 6th Duke of Bedford, by his second wife, Lady Georgiana Gordon.
 She was the mother of Louisa Montagu Douglas Scott, Duchess of Buccleuch, and therefore the paternal great grandmother of Princess Alice, Duchess of Gloucester, and the maternal 2nd great-grandmother of Prince William of Gloucester and Prince Richard, Duke of Gloucester.
 She was also the mother of James Hamilton, 2nd Duke of Abercorn, and therefore the paternal great-grandmother of Cynthia Spencer, Countess Spencer, and the paternal 3rd great-grandmother of Diana, Princess of Wales, and the maternal 4th great-grandmother of Prince William, Duke of Cambridge, and Prince Harry.
 Through her daughter Lady Louisa Hamilton she also is the maternal 3rd great-grandmother of Sarah, Duchess of York.
Duchess of Cambridge is the principal courtesy title held by the wife of the Duke of Cambridge.
 The title is legally gained upon marriage and is forfeited upon divorce.
 Five of the eight Dukes of Cambridge did not marry or morganate, and thus there are only three Duchesses of Cambridge including the current Duchess, Catherine, wife of Prince William, Duke of Cambridge.
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.
The 2011 royal tour of Canada by Prince William, Duke of Cambridge, and Catherine, Duchess of Cambridge, took place between 30 June and 8 July 2011.
 The tour saw the newlywed couple visit all of Canada's regions.
 It was the first such tour undertaken by the Duke and Duchess since their marriage two months prior, and the first duties the couple carried out as members of the Canadian Royal Family.
 The tour was followed by more than 1,300 accredited media.
 It included the first use of the Duke of Cambridge's royal standard for Canada, the first Canadian citizenship ceremony attended by royalty, Canada Day ceremonies attended by approximately 800,000 people, and many smaller events across the country.
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.
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.
Amanda Pullinger is the Chief Executive Officer of 100 Women in Finance, formerly 100 Women in Hedge Funds.
 Ms. Pullinger has led the organization in its growth from a few hundred members in New York to more than 15,000 members in 21 cities globally.
 100 Women launched its new name and branding at the Closing Bell of the NYSE on December 14, 2016 In 2009, she succeeded in bringing in Britain’s Prince William, Duke of Cambridge as the Patron of 100 Women in Hedge Funds.
 Ms. Pullinger welcomed The Duke and Duchess of Cambridge to the 100WHF's London Gala in 2011.
 In late 2012, it was announced that the Duke and Duchess of Cambridge, and Prince Harry would all be Patrons of 100WHF's Philanthropic Initiatives beginning in January 2013.
 In October 2013, a day after the Royal Christening of Prince George, Ms. Pullinger welcomed HRH The Duchess of Cambridge to 100WHF's London Gala for the benefit of Action on Addiction.
 She then welcomed HRH The Duchess of Cambridge to 100WHF's 2015 Gala in London for the benefit of The Art Room.
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.
Baron Carrickfergus is a title in the Peerage of the United Kingdom, referring to Carrickfergus in County Antrim, Northern Ireland.
 Its current holder, since its creation on 29 April 2011, is Prince William, Duke of Cambridge, who was granted the title as a personal gift, by Queen Elizabeth II, on the day of his marriage to Catherine Middleton.
 On the same day he was also created Duke of Cambridge and Earl of Strathearn, with his bride becoming Her Royal Highness The Duchess of Cambridge as well as Countess of Strathearn and Baroness Carrickfergus as a result of the marriage.
 Traditionally, when male members of the British royal family marry, they are granted at least one peerage.
 Catherine uses the title "Lady Carrickfergus" in a fuller version of her titles and styles, "Her Royal Highness The Duchess of Cambridge, Countess of Strathearn and Lady Carrickfergus".