[9] She also has another younger half-brother, Shawn Farrell, who played baseball and football at Notre Dame High School outside of Los Angeles.

Former top 100 player Francisco González, the head of tennis at the club, recognized Stephens had impressive ability given her limited experience and recommended her to pursue more rigorous training opportunities.

They became just the second pair of girls to win three Grand Slam tournament doubles titles in one season after Corina Morariu and Ludmila Varmužová in 1995.

[3] In March 2010, Stephens qualified for the Indian Wells Open to make her WTA Tour main-draw debut a week before turning 17.

[56] Stephens built on this momentum with a third-round appearance in her Wimbledon main-draw debut, which was highlighted by an upset of 23rd seed Petra Cetkovská.

13 Ana Ivanovic, after struggling with a torn abdominal muscle, which was initially injured during her fourth-round loss at the French Open a few months earlier.

Williams entered the semifinal on a 20 match win streak, while multiple betting websites listed the 19-year-old Stephens as at least an 11-to-1 underdog.

[67] Following the Australian Open, Stephens was forced to miss the United States' quarterfinal Fed Cup tie after aggravating her abdominal injury during her deep run at the tournament.

[69] Despite these struggles, Stephens produced another good Grand Slam tournament result at the French Open, where she defeated three unseeded opponents – none ranked higher than No.

After losing to an up-and-coming Caroline Garcia and picking up a win against Virginie Razzano, Stephens and her partner Madison Keys lost to the two of them in the final doubles match to relegate the United States into World Group II the following year.

[89] Stephens then improved on that result with a quarterfinal appearance at the Miami Open, which included a win over rival Madison Keys in their first encounter.

She attended several WTA events in the United States including Indian Wells, the Miami, and Charleston, where she interviewed fellow tennis players and also provided analysis.

This stretch notably included two matches at the year-end Elite Trophy as well as two singles rubbers in the Fed Cup final against Belarus.

[142] At the US Open, Stephens was unable to defend her title, losing to Anastasija Sevastova in the quarterfinals in a rematch of last year's meeting at this tournament in the same round.

Her best Grand Slam performance was a quarterfinal loss to Johanna Konta at the French Open, where she could not defend her runner-up finish from the previous season.

[221] Seeded second at the first edition of the Mérida Open in Mexico, Stephens got her first win of the year by beating qualifier Léolia Jeanjean in the first round.

[243][244][245][246] She grew up as a fan of the Williams sisters, but had lost some of her interest in them after they did not sign autographs at a Fed Cup tie that Stephens attended at age 12.

The match win and her run into a Grand Slam singles semifinal garnered international attention and put her on the cusp of cracking the top 10 of the WTA rankings later in the season.

[68] With Serena entering the match in excellent form and also having defeated her much younger opponent earlier that month, Stephens was listed as high as a 16-to-1 underdog.

"[252] International Tennis Hall of Famer Chris Evert has praised their rivalry, saying, "I liked [their match in the 2018 Canadian Open final] a lot, because that is a contrast in personalities and styles, in moods, in coaches.

[255] Stephens then won their next two meetings in early 2013, including a first round match at the Australian Open as part of her breakthrough semifinal run at the event.

This score is average compared to other women's tennis players, and rates similarly to fellow Grand Slam tournament winners Justine Henin and Victoria Azarenka.

Her former junior coach Chris Evert has questioned her motivation on multiple occasions and attributed stretches of inconsistency at various times in her career to her mentality.

On the contrary, Stephens has also shown the ability to use her mindset of not worrying about disappointing outcomes to bounce back from injury and poor tournaments.

Stephens replaced him with Paul Annacone, who is better known for coaching two of the greatest players in tennis history in Pete Sampras and Roger Federer.

[291][292][293] Stephens has previously signed a deal with the American Express credit card company and was formerly an endorser of the Listerine mouthwash product.

[295] Moreover, Stephens has worked with Time Warner Cable as part of their Connect a Million Minds campaign to motivate the importance of education in science, technology, engineering, and math (STEM) fields.

[297] Stephens is of Trinidadian descent through her maternal grandfather Noel Smith, who came to the United States from Trinidad to pursue a career as a doctor.

Although she disliked that they were uninterested in signing autographs at a match she attended and has also commented that neither of them tried to serve as one of her mentors, Stephens has stated she developed a good relationship with the Williams sisters.

[301][14][302] Stephens has been married to United States national soccer team player Jozy Altidore, who was also one of her childhood friends in Florida, since January 1, 2022.