Celebrity Rachel Dolezal's Mother: Brother's Sex Abuse Charges Are A "Malicious False Lie" Joshua Dolezal faces trial this summer on allegations he sexually abused a female sibling By Diane Herbst and Christine Pelisek Published on June 16, 2015 07:20 AM Share Tweet Pin Email Photo: (Colin Mulvany/The Spokesman-Review/AP The dispute over former NAACP president Rachel Dolezal’s race isn t the only challenge facing the family. A trial is set for August in a case against Dolezal’s brother Joshua who is accused of sexually abusing a female sibling in 2001 or 2002 when the child was six or seven years old, according to court documents obtained by PEOPLE. Joshua, a college professor in Pella, Iowa, was charged with four felony counts of sexual assault on a child in 2013 by the Clear Creek County District Attorney’s Office. The abuse allegedly occurred when the family lived in Colorado. The district attorney’s office would not comment on the case. Joshua and his attorney did not return calls for comment. “That is all a malicious false lie,” Dolezal’s mother Ruthanne tells PEOPLE. “[Rachel] is the one who initiated it. We know it is not true.” The sexual abuse claims have come under the spotlight less than a week after Dolezal was accused of pretending to be a black woman for years, when her parents say she is white Dolezal, who resigned her post as NAACP president of the Spokane chapter Monday amid the controversy, has said the fracas over her ethnicity was planted by her parents as the Colorado case comes to trial. Dolezal’s parents dispute her claim. “We did not initiate it but when we were asked we were honest,” says Ruthanne. “We didn’t participate in the lies. We couldn’t. We won’t.” The sexual abuse allegations were brought to the attention of Colorado authorities in July of 2013. According to a search warrant affidavit, Joshua’s accuser came forward because “Joshua Dolezal has a one year-old daughter and [victim] does not want the daughter to be victimized.” During a series of interviews, the alleged victim, now 20, told detectives that Joshua, who is 19-years-older, made the victim undress in front of him and forced the victim to perform oral sex on him. According to the report, the accuser told adopted mother Ruthanne about the alleged abuse but she “did not believe [victim] and told [victim] to stop telling lies.” Joshua allegedly told his accuser, “Don t tell anyone or ‘I’ll hurt you.'” The attacks, the victim said, ended when Joshua returned to college. Ruthanne says the victim suffers from reactive attachment disorder, a condition in which a child can’t bond with a parent or caregiver, and “seeks to cause trouble in the family.” “The aligning with Rachel on this is a very bad combination,” she says. “Our son wasn’t even home a lot of the time it was alleged it was happening,” she says, “and I was a stay-at-home mother and very attentive to the kids because of her disorder. I never left her at home with our son or anything like that.” Ezra Dolezal, 22, one of Dolezal’s adopted brothers, tells PEOPLE that Rachel has made things up about their eldest brother abusing the victim. “It’s more false statements,” says Ezra. “it’s a really horrible situation.” Rachel and Josh “used to have a really good relationship, until Rachel decided to tear our family apart,” says Ezra as he recalled Rachel taking their parents to court in an effort to adopt another adopted brother, Isaiah. That effort, Ezra says, was wrought with false accusations by Rachel levied against their parents. “Josh called Rachel out on that and told her it was wrong what she did, taking my parents to court over my brother, and Rachel didn’t like that,” Ezra says. “Basically Rachel has been constantly trying to get at Josh since then.” According to the report, Dolezal was contacted in September of 2013 about her adopted sibling’s claims. She told authorities that her sibling informed her about the abuse three months earlier, in June. “She said that [victim] told her what had happened to [victim] with Joshua Dolezal in Colorado and [Rachel] had promised to help [victim] seek closure,” the report states. According to the court document, Joshua’s attorney, Aaron Hamrock, told Clear Creek County Sheriff detective Al Billinger that the Missouri Department of Social Services had requested that the Iowa Department of Human Services interview Joshua about the allegations. Billinger wrote that Hamrock received a letter from a Missouri social services caseworker informing him that “there was no basis for the allegations.” RELATED VIDEO: Spokane NAACP President Quits Over Race Controversy “Aaron Hamrock advised that the allegations had already been investigated and that he does not think that Joshua Dolezal should have to submit to another interview regarding the allegations,” the report states. Billinger said Hamrock gave him the letter from the Missouri service, which found the report of abuse to be “unsubstantiated.” “This letter does not list the facts on which the determination was based,” wrote Billinger. Billinger wrote that he reached out to the caseworker with the Iowa Department of Human Services who interviewed Joshua Dolezal in 2011 for the Missouri Department of Social Services “but she has not returned any of my calls,” he said.