The 21-year-old hurdler became the first woman to break 52 seconds in the 400m hurdles, setting a world record of 51.90.
McLaughlin beat the previous record set by Dalilah Muhammad by .26 seconds.
Here are five things to know about McLaughlin while you watch the Tokyo games.
1. McLaughlin hails from the Middlesex County borough of Dunellen, and all of her family members are runners.
Her father Willie McLaughlin, ran for East Orange and went on to become a semi-finalist in the 400 meters in the 1984 Olympic trials. Her mom, Mary, ran in high school.
McLaughlin's older brother, Taylor McLaughling, won the silver in the 400 m hurdles at the 2016 IAAF World U20 Championships. Her older sister, Morgan McLaughlin, was a standout runner at St. Peter's University. The three have a younger brother, Ryan, who's also a runner.
2. McLaughlin ran at Union Catholic High School in Scotch Plains -- as did her siblings -- and went on to compete for the University of Kentucky.
She qualified for her first Olympic games in 2016 after placing third in the 400m hurdles. McLaughlin also competed in the Rio games when she was 16, making her Team USA's youngest Olympic competitor since 1972.
Two years later, McLaughlin signed a sponsorship deal with New Balance and turned pro.
3. McLaughlin is dating former NFL star Andre Levrone Jr., who retired last year after playing for the Jacksonville Jaguars.
4. McLaughlin is a devout Christian. Last February, she shared a passage from the Book of Colossians, and said the reason for her pure joy and happiness is because of Christ inside of her.
5. The athlete has a YouTube channel, where she posts videos on cooking, makeup, modeling gigs, her road to the Olympics and more.
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