Cape Verde has never won an Olympic medal, and despite the country sending only four swimmers to the 2020 Olympics, Latroya, Troy and Jayla Pina have all been chosen.
They have never been to the archipelago nation off the north-west of Africa, but their mother was born there.
The siblings hope to follow in the footsteps of Simone Manuel, who in 2016, became the first black female swimmer to win an Olympic gold medal.
Video produced by Daniel South and Ian Cartwright
Photo credit: Sports Hochi Japan
Listen to The Documentary on the BBC iPlayer.
Main image credit: Getty Images
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