4:30 PM PT -- TMZ has obtained arrest docs in Hayden's case ... and Hayden's daughter is now backing up the allegations. She told investigators Hayden took her virginity in March, 2013 when she was 11-years-old. She said she was orally and vaginally raped almost daily, but did not report it because he threatened her physically.
According to the docs, the victim says Hayden told her, "Don't tell them nothing, because I'm all you got."
Will Hayden has been arrested again -- this time cops are adding a charge of child rape in the molestation case he's already facing .
Law enforcement sources tell us the investigation led the East Baton Rouge Sheriff's Department to tack on a charge of aggravated rape of a child. An arrest warrant was issued yesterday... and cops, aided by U.S. Marshals, nabbed Hayden in Livingston, LA.
Hayden told us after the initial arrest that his ex-girlfriend -- and mother of the child -- was making false allegations to get back at him for ending their relationship.