Heidi Montag, star of 'The Hills: New Beginnings' does not believe that her father molested her stepsister, despite him recently pleading guilty to the charges.

According to the 2015 arrest affidavit for William Montag obtained exclusively by Radar, Heidi, now 33, spoke to Colorado police via telephone on December 9, 2014.

According to the docs, the MTV star "didn't believe [redacted]…from childhood, she recalled [redacted] being mean to her."

But her father's alleged victim, Carissa Berlet is unimpressed with her stepsister's statement:

"My first thought is, she didn't live in our household," Carissa told Radar of Heidi, who grew up in her mother's home. "Nobody knows what goes on behind closed doors."

"It's her dad — I get it…You defend your loved ones, so I understand. But it's also upsetting to make a statement about something that she was not actively involved in," explained Carissa, 38.

 "She wasn't there. She doesn't know."

Mr. Montag pleaded guilty to child abuse back in 2016, and was sentenced to four years probation.