Farrah's House Of Horrors: Teen Mom's Father Once Arrested On Felony Weapons Charges

Farrah Abraham's volatile relationship with her parents has been well documented on Teen Mom OG. But now, RadarOnline.com can reveal that the nasty fighting runs deeper than anyone knows.

When Farrah was a pregnant teenager, her father, Michael Abraham, was arrested and charged for going armed with intent, a class D felony, RadarOnline.com has exclusively discovered.

According to Iowa's Pottawattamie County District Court documents, Michael, 59, "did go armed with a dangerous weapon with the intent to use said weapon without justification against the person of another" on September 21, 2008.

READ THE SHOCKING COURT PAPERS

Involved in the incident were Farrah, then 17, and her baby daddy to be, Derek Underwood. (Derek tragically passed away in a car wreck just three months later at 18.)

Michael pled not guilty, and a trial was slated to begin on January 13. However, the charges were dismissed days after Derek's death.

The grandfather of Farrah's 7-year-old daughter Sophia tells RadarOnline.com that the scary altercation was related to a story chronicled in the reality star's memoir, My Teenage Dream Ended.

In the 2012 book, Farrah claimed her dad "snapped" when he caught her with Derek in her bedroom, and threatened the teen boy with a knife.

"Yes, I knew she was pregnant at the time," Michael confirms to RadarOnline.com of his daughter, who gave birth to Sophia in February 2009. "I'm going to discuss it in my upcoming book."

Farrah's mom, Debra Danielsen, also has a history of handcuffs. In January 2010, Debra, 58, was arrested and charged with assault following an altercation with her daughter.

And, of course, Farrah is no stranger to nasty physical fights. On the last season of her MTV series, she was caught on camera pushing a producer after an argument.