Serena Williams says sister Venus' health is more important than tennis.
Serena Williams says her sister Venus Williams' decision to withdraw from the U.S. Open because of Sjorgen's Syndrome has given her a little perspective.
The tennis champ, who has had her own health scares recently, tells PEOPLE her sister's diagnosis made her realize that life "isn't all about tennis."
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"I love playing tennis and I love the battle," she says, "but I realize that life is so precious."
Serena adds that Venus is in good spirits and she's staying positive.
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Sjorgen's Syndrome is an autoimmune disease that causes fatigue and joint pain. Some four millions Americans suffer from the condition.
Get well, Venus!