Todd Palin has filed for divorce from Sarah Palin, the former governor of Alaska and GOP vice presidential candidate, citing "incompatibility of temperament” and that “they find it impossible to live together as husband and wife."

Todd Palin, 55, asked to dissolve the couple's 31-year marriage in a filing submitted Friday in Anchorage Superior Court. The paperwork was submitted on Sept. 6, eight days after the couple's anniversary.

The filing, first reported by the Anchorage Daily News, only uses initials but details the couple’s marriage date and the birth date of their 11-year-old son, Trig, and asks for an equal separation of assets and debts.

The two have been married since 1988 and have five children: Track, Trig, Bristol, Willow and Piper. Todd Palin's filing asks for shared custody of Trig, who has Down Syndrome.

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Sarah Palin, also 55, was elected governor of Alaska in 2006 and resigned in 2009, before the end of her four-year term. She also served as the late Sen. John McCain's running mate in the 2008 presidential election, ultimately losing the election to Barack Obama and Joe Biden.

Todd Palin, unlike his famous political wife, has largely steered clear of headlines since she burst on the national scene during 2008 presidential election cycle.

He was in a snowmobile accident in 2016, in which he suffered broken ribs and a collapsed lung, a broken shoulder blade, a broken clavicle, and leg injuries. It was one of the few times the husband made headlines.

Although that’s not to say he lacked any role in his wife’s political life. E-mails uncovered by MSNBC in 2011 showed that Todd Palin regularly communicated with senior Alaska state officials on a wide range of topics.

They included online chats about potential board appointees, constituent complaints, use of the state jet, oil and gas production, marine regulation, gas pipeline bids, post-secondary education, wildfires, native Alaskan issues, the state effort to save the Matanuska Maid dairy, budget planning, potential budget vetoes, oil shale leasing, staffing at the mansion, pier diem payments to the governor for travel, potential cuts to the governor's staff, Bureau of Land Management land transfers and trespass issues.

The couple's children have also lived in and out of the spotlight over the years.

Track Palin, their eldest son, was sentenced to a year in custody last year after a female acquaintance said he told her that she could not leave his house in Wasilla, took away her phone and then hit her in the head.

In December 2017, Track Palin was accused of breaking into his parents' home and leaving Todd bleeding from cuts on his head, authorities said. He pleaded guilty in June 2018 to a lesser charge in veterans court.

The couple's daughter Bristol Palin briefly starred in MTV's "Teen Mom" franchise but quit the series in April. She said in her announcement that the reality series wasn't a good fit for her and that "walking away from this show allows God to rebuild me (and my little fam) in the right direction."

Bristol Palin was 17 when she found out she was pregnant with her son, Tripp, who she had with former fiancé, Levi Johnston. She also has two daughters, Sailor Grace and Atlee Bay, with former husband, Dakota Meyer.

Neither Todd nor Sarah Palin could immediately be reached by NBC News for comment.