"This is a painful and heartbreaking time," Shriver said in a statement. "As a mother, my concern is for the children. I ask for compassion, respect and privacy as my children and I try to rebuild our lives and heal.
"I will have no further comment."
Shriver, 55, celebrated her 25th wedding anniversary to Schwarzenegger, 63, on April 26; they have four children, ranging in ages from 14 to 21.
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