Sara Evans' ex-husband fears kids will be harmed on tour

Evan Agostini/AP

Craig Schelske and country singer Sara Evans, pictured in 2005, split the following year.

More than four years after Sara Evans filed for divorce from her husband of 13 years, the former couple's ugly custody battle continues to take nasty turns.

Just this week, Evans' ex-husband, Craig Schelske, reportedly filed court papers arguing that he should have joint custody of their children due to the potential "harm" they'll face on the singer's upcoming tour.

Evans and Schelske have three kids together: 11-year-old Avery, 8-year-old Olivia and 6-year-old Jack. The country singer, who remarried in 2008, currently has full custody.

But Schelske wants to "protect the children from the likelihood of substantial harm" when Evans, 40, hits the road in June, according to TMZ.com.

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In March, Evans and new husband, Jay Barker, told People they plan to take their blended family ? Barker has four young kids of his own with his ex-wife ? to live on the singer's tour bus this summer.

Court documents filed Wednesday reportedly claim that Schelske, who had joined Evans on tour during their relationship, "has firsthand knowledge that the children are exposed to inappropriate conduct, spend little time with [Evans], and are placed in a party atmosphere with excessive drinking and drug use."

It is also alleged that Evans has "encouraged and condoned underage drinking."

This isn't the first time Schelske has made some potentially damaging allegations against the singer. Following their split, he accused her of having several affairs with various musicians, including Kenny Chesney and the members of 3 Doors Down. The trysts were later denied.

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Evans, however, had also accused her ex of affairs, as well as having a penchant for pornography and committing verbal and emotional abuse.

The country star dropped out of "Dancing with the Stars" in 2006 when she decided to file for divorce.

Last year, Evans obtained a temporary restraining order against Schelske, barring him from using the media to make derogatory statements about her or accusations related to their divorce.

A rep for Evans has not yet responded to a request for comment.

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