As young girls, the family moved to Compton in California. There, the two sisters trained for hours on municipal courts urged on by their father.
With Richard opting not to enter the pair in junior tournaments as teenagers - partly due to alleged racism from other parents - Venus turned pro in 1994 a year before Serena. Venus was the first to beat established players and reached the 1997 US Open final where she lost to Martina Hingis.
Venus won a number of WTA Tour titles in 1998 with Serena eventually claiming her first at the Open GDF Suez in Paris on indoor hard courts in February 1999, beating Amelie Mauresmo in the final. The younger Williams sister then stunned Steffi Graf, coming to the end of her 12-year dominance of the sport, in the Indian Wells final.
Serena was the first of the sisters to win a major, taking the 1999 US Open that year by defeating Hingis in straight sets. Venus then took over with Wimbledon and US Open titles in 2000 and 2001, as well as Olympic gold at Sydney 2000 where she and Serena won doubles gold.
But Serena soon emerged from her sister's shadow, winning four consecutive Grand Slam singles tournaments - known as the 'Serena Slam' - from the 2002 French Open to the 2003 Australian Open. Venus was the beaten finalist on each occasion.
She went on to win 23 Slam singles events - seven Australian Opens, seven Wimbledon, six US Opens and three French Opens - one more than fellow 'GOAT' candidate Graf and the most of any woman in the Open era.
Serena - who demolished Maria Sharapova to win her sole Olympic singles title at London 2012 - was carrying her first child when she won the 2017 Australian Open which proved to be her last Slam singles success.
After giving birth to Olympia, she returned to tennis and made four Slam finals - the Wimbledon and US Open finals in 2018 and 2019 - but lost all four. In January 2020, Serena claimed her first, and last, title as a mother at the Auckland Open.
As well as their success in singles - Venus collected seven Slam titles - the siblings were just as formidable in doubles. They won three Olympic golds together - at Sydney, Beijing 2008 and London 2012 - and 14 Slam titles as a pairing.
Serena Williams "evolving away from tennis"
While not expressly announcing her retirement from tennis, Serena Williams wrote in Vogue ahead of the 2022 US Open, "I'm here to tell you that I'm evolving away from tennis toward other things that are important to me."
In her last Slam in New York, she rolled back the years to defeat then world number two Anett Kontaveit before going out to Ajla Tomljanovic which would prove to be her final match.
Now a mother of two, having had a second daughter - Adira - in August 2023, Williams is involved in philanthropy and invests in female and BIPOC-owned business ventures.