Venus Williams is one win away from returning to the Wimbledon final for the first time since 2009.
On that occasion she lost to younger sister Serena and the 36-year-old is on target to face her sibling again after defeating Yaroslava Shvedova of Kazakhstan 7-6 6-2 in the quarter-finals.
Venus will face fourth seed Angelique Kerber in tonight's semi-finals, after the German's win over Simona Halep 7-5 7-6. Serena reached the last four with a 6-4 6-4 victory over Russia's Anastasia Pavlyuchenkova and will play unseeded Elena Vesnina, who beat Dominika Cibulkova 6-2 6-2.
Asked about playing her sister in their fourth Wimbledon title-decider, Serena said: "It would be great. Obviously, she's such a tough opponent.
"I want her to win so bad - obviously not in the final if I'm there - but, if I'm not there, I desperately want her to win."
Serena leads their battles 16-11 overall and 4-2 at Wimbledon. Venus defeated Serena in the 2000 semi-finals en route to her first title and again in the 2008 final. Serena beat Venus in the 2002, '03 and '09 finals, and in the fourth round last year.
Venus, who has struggled with Sjogren's syndrome - a condition that can cause joint pain and saps energy, is aiming to win her fourth title at All England Club after success in 2001, '05 and '07.
"You can't always have this big moment," Venus said. "If you're Serena Williams, I guess that happens a lot. As Venus Williams, this is an awesome day."