"We stopped ballet pretty quickly," Eliza said. "Fencing took us over completely."
Each started on a different weapon, with Robert in saber. That they all wound up in saber owed to both skill set and finances, as it proved cheaper to have them all use the same type of sword.
That, of course, threatened to exacerbate their sibling rivalries.
"We decided we weren't going to get too hung up if we won or lost against each other," Eliza said.
Their older sister, Katie, was involved in the home schooling competition but escaped the swordplay. She did not fence and went to the University of Chicago, where she now works in the psychology department.
Eliza expects Gracie, who also is competing in the Chicago World Cup, to follow a path similar to hers, studying political philosophy, concentrating on college through her 2016 graduation and then thinking about a shot at the 2020 Olympics. Robert, also studying political philosophy, is likely to go straight toward a doctorate and a career in academe.
"Robert likes fencing but doesn't live for it," Cynthia Stone said. "Gracie loves it, and Eliza lives for it right now."
So Eliza has turned down a medical school "catch-up" program at Columbia University this year because of possible conflicts with fencing.
"After my junior year, I decided I wanted to continue fencing beyond college," Eliza said. "I realized I couldn't live with myself if I stopped."
Korfanty World Cup
Where: Illinois-Chicago, Flames Athletic Center, 839 W. Roosevelt Road
When: Friday, 9 a.m, women's qualification, 1 p.m., men's qualification; Saturday, 9 a.m., women's elimination rounds; 1:40 p.m., men's elimination rounds; 6:30, women's and men's semifinals and finals; Sunday, 8:20 a.m., women's team preliminaries; noon, men's team preliminaries; 6 p.m., women's and men's team bronze- and gold-medal matches.
Who: Women — 2012 Olympic gold medalist Kim Ji-Yeon of South Korea and bronze medalist Olga Kharlan of Ukraine; 2004 and '08 Olympic champion Mariel Zagunis of Portland, Ore.; reigning NCAA champion Eliza Stone of Chicago. Men — All three 2012 Olympic medalists: Aron Szilagyi of Hungary, Diego Occhiuzzi of Italy, Nikolay Kovalev of Russia; Daryl Homer of New York City, sixth in the London Games.