Sydney Michelle McLaughlin (born August 7, 1999) is an American hurdler and sprinter. McLaughlin belongs to an athletic family. Her father Willie was a semi-finalist in the 400 meters at the 1984 Olympic Trials, her mother Mary was a runner in high school, and her older brother Taylor won silver in the 400-meter hurdles at the 2016 IAAF World U20 Championships. A resident of Dunellen, New Jersey, she is a member of the class of 2017 at Union Catholic Regional High School in Scotch Plains and has been successful academically. McLaughlin took up running at an early age, following Taylor and their older sister Morgan. McLaughlin placed a close second behind Shamier Little in the 400- meter hurdles at the national junior (under-20) championships in 2014; her time of 55.63 was a national high school freshman record and a world age-14 best. She would have qualified to represent the United States at the 2014 IAAF World Junior Championships but was a year too young to be eligible. McLaughlin also set a world age group best (13.34) in the 100-meter hurdles over 76.2 cm (2 ft 6 in) hurdles that summer. McLaughlin improved her 400-meter hurdles best to 55.28 at the 2015 national youth trials; the time was an age 15 world best and ranked second on the all-time world youth list behind Leslie Maxie 's world youth best (and national high school record) of 55.20 set in 1984. She qualified for the 2015 IAAF World Youth Championship in Cali, Colombia, where she won gold in 55.94; she finished the year as the world youth and junior leader in the event. McLaughlin won the 400-meter hurdles in 54.46 at the 2016 New Balance national outdoor high school championships; the time broke Maxie's prep record and world youth best, as well as Lashinda Demus's American junior record of 54.70. In addition, she ran on Union Catholic's team in the Swedish medley relay, running a fast 50.93 split for 400 meters as the team set a new high school record of 2:07.99. McLaughlin won the USATF junior championship in 54.54 the following week; in recognition of her accomplishments, she was named Gatorade National Girls Athletic of the Year. McLaughlin won her heat (55.46) and semi-final (55.23) in the 400-meter hurdles at the 2016 United States Olympic Trials. In the final she placed third in 54.15, setting a new world youth best and world junior record and qualifying for the Olympics in Rio de Janeiro. McLaughlin is the youngest athlete to make the American Olympic track and field team since Carol Lewis and Denean Howard qualfied for the boycotted Moscow Olympics in 1980. At the Olympics she placed 5th in her semi-final heat, failing to advance to the finals. In November 2016, McLaughlin signed a National Letter of Intent to attend the University of Kenyucky and compete for their track and field program. McLaughlin was part of an American Records quartet that broke the indoor distance medley relay world record with a time of 10:40.31, set at the New Balance Indoor Grand Prix on January 28, 2017. The splits for the four legs were: 3:18.40 (1200 m) by Olympic medalist Emma Coburn,52.32 (400 m) by McLaughlin, 2:01.92 (800 m) by Brenda Martinez, and 4:27.66 (1600 m) by Olympic medalist and former world 1500m champion Jenny Simpson. Later that indoor season, McLaughlin lowered her own national 400-meter record to a 51.61 at the New Balance Nationals in New York City on March 12, 2017. In April 2017, McLaughlin continued the positive momentum from the 2017 indoor campaign by opening her outdoor season in style—breaking the 300m hurdles national high school record at the Arcadia Invitational running 38.90. The record was previously held by Lashinda Demus who ran 39.98 in 2001. The record was the first ever attempt over 300m hurdles for McLaughlin as high school track meets in New Jersey do not contest the 300m hurdles. Her time of 38.90 is a North American Record and number 2 all-time worldwide behind Zuzana Hejnova who ran 38.16 in 2013. Later that month, McLaughlin ran the fastest ever high school girls (400m) relay split during the Championship of America high school girls 4x400 at the 123rd Penn Relays. After taking the baton at the back of an eight-team field, McLaughlin posted a split of 50.37, passing five teams to lead her Union Catholic relay team to a third-place finish in 3:38.92. She bettered this mark at the New Balance Nationals Outdoor Meet on June 18, 2017. Taking the baton in 6th place on the final handoff, she passed five runners to lead Union Catholic to victory, posting a split of 49.8 seconds. In March 2018, McLaughlin set the world junior 400-meter record in (50.36) at the 2018 NCAA Division 1 Indoor Track and Field Championships. On May 13, 2018, McLaughlin broke the collegiate and NCAA records in the 400-meter hurdles, running 52.75 to win the event in her first SEC championship appearance. In October 2018 she turned professional, and signed with the New Balance team