The paper also reported this week that Ehrlick has served time in prison and been convicted of battery and burglary. According to the Statesman, Ehrlick is banned from spending time alone with Robert's half-sister.
Police have kept mum so far on the family's legal troubles and their involvement with the search for Robert.
"The previous family history and the connection to Robert's case, if any, is ... part of the investigation," Boise Police spokeswoman Lynn Hightower told ABCNews.com last week.
Robert's aunt, Trisha Burrill has been acting as the family's spokeswoman. She told ABC's Boise affiliate KIVI that the family's troubled history should not be a focus for police or the media.
"We do not know why people think any of this matters," she said.