Sisters Tiffany Porter and Cindy Ofili both qualified for the semi-final of the women's 100m hurdles at the World Athletics Championships in Beijing this morning.
Ofili was first up as the younger of both GB athletes - who were born in the USA - finished fourth in a time of 12.97s to advance, with American Brianna Rollins coming first in 12.67s.
Porter rose to the sibling rivalry, however, as the reigning European champion barely broke sweat to win her heat by clocking 12.73s.
Ofili, who had never been inside the United Kingdom until June, finished second to her older sister in the qualification race in Birmingham earlier this summer.
The semi-finals are scheduled to begin from 12.25pm on Friday afternoon.