Five Finger Death Punch Singer Terrorizing His Whole Family ... Says Sister

8/13/2015 12:30 AM PDT

Five Finger Death Punch Singer -- Sister Filed Restraining Order In The Past

EXCLUSIVE

Five Finger Death Punch singer Ivan Moody made his own sister and mother fear for their lives ... according to docs obtained by TMZ.

Sandra Dykes, Moody's younger sister, got a restraining order against him last September after she says Ivan harassed her, and made threats toward their mom.

In the docs Dykes claims Moody has a history of violence with women that spirals out of control when he drinks and drugs. She says she was forced to take action when Moody started falsely accusing her, their mother, and even his own daughter ... of stealing his money.

A judge granted Dykes and her 2 kids restraining orders. She says her mom and niece are filing for their own.

As we previously reported, Moody's wife filed for divorce this week with disturbing abuse allegations.