Katy Winn / Getty Images file

Dennis Quaid filed for divorce from wife Kimberly Buffington-Quaid on Friday.

Dennis Quaid is pulling his half of the plug. About a month and a half after wife Kimberly filed for a legal separation, the "Vegas" star has filed for divorce, citing irreconcilable differences and requesting joint legal and physical custody of their 5-year-old twins. 

He also expressed his willingness to pay spousal support, according to the petition filed today in L.A. Superior Court and obtained by E! News. 

View the documents 

October marked the second time Kimberly started official split proceedings, the couple having attempted a reconciliation after her initial attempt in March. The future ex-Mrs. Quaid, meanwhile, has asked for joint legal and primary physical custody of the children. 

Vegas has a full-season order from CBS 

In the court documents, Quaid lists their date of separation as Oct. 1. He also asks that he and his ex be responsible for their own legal fees. 

This was Quaid's third marriage, his second, to Meg Ryan, came to an end in 2001 after 10 years. 

Dennis Quaid opens up about 1980s cocaine habit 

He and Kimberly tied the knot July 4, 2004. Their son Thomas and daughter Zoe Grace were born via gestational carrier on Nov. 8, 2007.

Big celebrity splits 

The infants suffered life-threatening health scares just days after they were born when they received an accidental overdose of blood thinners at Cedars-Sinai Medical Center. The Quaids sued the hospital and the maker of the drugs, citing negligent packaging practices, and ultimately reached settlements with both.

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George Frey / EPA file

Dennis Quaid and his wife Kimberly in Park City, Utah, in January.

All good things come to an end. Real estate agent Kimberly Buffington-Quaid has filed for legal separation from actor Dennis Quaid, her husband of eight years, TMZ reports. She is asking for joint legal and sole physical custody of their 4-year-old twins, Thomas and Zoe.

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(The siblings almost died as newborns in 2007 when the medical staff at Cedars-Sinai Medical Center accidentally gave them an overdose of the drug Heparin. After filing a lawsuit with the hospital and the drug manufacturer, the couple was awarded $750,000.)

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Repped by power attorney Laura Wasser, Buffington-Quaid is also seeking spousal support and legal fees. She first filed for divorce in March 2012 but withdrew her petition two months later. "Kimberly ... wants out of the marriage," a source close to the couple tells TMZ. "He's not a good husband."

PHOTOS: Most expensive divorces in Hollywood

Prior to marrying Buffington-Quaid, the "Vegas" actor, 58, was wed to "Sleeping in Seattle" star Meg Ryan, 50; they divorced in 2001 and are parents to "Hunger Games" star Jack, 20. Quaid was first married to "Halloween" actress PJ Soles, 62; they divorced in 1983.

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