The former couple are the parents of 4-year-old twins, a son and daughter.
"Kimberly and Dennis Quaid have decided to legally separate after eight years of marriage. They ask that their privacy and the privacy of their family be respected during this difficult time," Quaid's representative told People.com.
Kimberly Quaid, a former real estate agent, filed for divorce in March, but reconciled with her husband the following month.
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