Heather Miriam Watson (born 19 May 1992) is a British tennis player and a Wimbledon Mixed Doubles Champion.
 She is a former British No.1 and current British No. 2 behind Johanna Konta.
The Williams sisters are two professional American tennis players: Venus Williams (b. 1980), a seven-time Grand Slam title winner (singles), and Serena Williams (b. 1981), twenty-three-time Grand Slam title winner (singles), both of whom were coached from an early age by their parents Richard Williams and Oracene Price.
 There is a noted professional rivalry between them – between the 2001 US Open and the 2017 Australian Open tournaments, they met in nine Grand Slam singles finals.
 They became the first two players, female or male, to play in 4 consecutive grand slam singles finals from the 2002 French Open to the 2003 Australian Open; Serena famously won all 4 to complete the first of two "Serena Slams".
 Between 2000 and 2016, a 17-year span, they collectively won 12 Wimbledon singles titles (Venus won 5 and Serena won 7).
 By winning the 2001 Australian Open women's doubles title, they became the 5th pair to complete the Career Doubles Grand Slam and the only pair to complete the Career Doubles Golden Slam.
 At the time, Venus and Serena were only 20 and 19 years old, respectively.
 Since then they have gone on to add another two Olympic gold medals in the 2008 Beijing Olympics and the 2012 London Olympics.
 Nearly a decade later, the duo would go on to win 4 consecutive grand slam doubles titles from 2009 Wimbledon through 2010 Roland Garros, which would catapult them to co-No.
 1 doubles players on 7 June 2010.
 Two weeks later, on 21 June 2010, Serena would hold the No. 1 singles ranking and Venus would be right behind her at No. 2 in singles.
 Their most recent grand slam doubles titles came at the 2012 Wimbledon & 2016 Wimbledon events.
 They remain very close, often watching each other's matches in support, even after one of them has been knocked out of a tournament.
Sandra Reynolds Price ("née" Reynolds; born 4 March 1934) is a former tennis player from South Africa who won four Grand Slam women's doubles championships and one Grand Slam mixed doubles championship.
 Her best Grand Slam singles result was reaching the 1960 Wimbledon final, losing to Maria Bueno 8–6, 6–0.
 Reynolds is the only female player from South Africa to have reached the Wimbledon singles final, and she is one of three to have reached a singles final in a Grand Slam.
 In 1961, she was seeded no. 1 for the Wimbledon Ladies Singles Championship, making her the only South African player (man or woman) ever to be seeded first in a Grand Slam singles event.
 She was the runner-up at the 1959 , losing to Sally Moore in the final.
 Price won the German Championships in 1960, 1961, and 1962.
 She was the runner-up at the 1959 Italian Championships, having defeated Bueno in a semifinal, then losing to Christine Truman in the final.
Pierre-Hugues Herbert and Édouard Roger-Vasselin were the defending champions but Roger-Vasselin decided not to participate.
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Judy Tegart Dalton (née Tegart; born 12 December 1937) is a retired professional tennis player from Australia who won nine Grand Slam doubles titles.
 She won at least one women's doubles title at each Grand Slam tournament, a "career Grand Slam".
 Five of her doubles titles were with Margaret Court.
 Tegart was the runner-up in 10 Grand Slam doubles tournaments.
Édouard Roger-Vasselin (] ; born 28 November 1983) is a male tennis player from France.
 He won the men's doubles title at Roland Garros in 2014, partnering Julien Benneteau.
 He is the son of 1983 French Open semifinalist Christophe Roger-Vasselin.
Daniel Nestor and Édouard Roger-Vasselin were the defending champions, but chose not to participate together.
 Nestor played alongside Aisam-ul-Haq Qureshi, but lost in the first round to Rohan Bopanna and Donald Young.
 Roger-Vasselin teamed up with Steve Johnson, but lost in the first round to Jamie Murray and Bruno Soares.
Daniel Nestor and Édouard Roger-Vasselin were the defending champions, but chose not to compete together.
 Nestor played alongside Vasek Pospisil, but lost in the semifinals to Ivan Dodig and Marcelo Melo.
 Roger-Vasselin teamed up with Julien Benneteau, but lost in the first round to Milos Raonic and Nenad Zimonjić.
Nicolas Mahut and Édouard Roger-Vasselin were the defending champions, but Roger-Vasselin chose not to participate.
 Mahut played alongside Sergiy Stakhovsky, but lost in the semifinals to Jonathan Erlich and Rajeev Ram.
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Łukasz Kubot and Édouard Roger-Vasselin were the defending champions, but Kubot chose not to participate this year.
 Roger-Vasselin played alongside Julien Benneteau, but lost in the first round to Marcus Daniell and Marcelo Demoliner.

Question: Who was first to win a Grand Slam doubles championship, Heather Watson or Édouard Roger-Vasselin?
Answer: Édouard Roger-Vasselin