One of his other brothers wrote a book about how their mother abused him years after Dave got out. So there is truth to it. Speaking of the abuse in the first book, WTF was up with his mom trapping him in the bathroom with bleach in the room? Or the part where she held his hand above a burning stove. Or the part where she took a dirty diaper and forced him to eat the shit in it.According to the book, when Dave was taken away from his mom, she found another one of her children to treat like shit, the one who corroborated Dave's story. Given how Dave basically described his siblings as being so grateful they weren't the punching bags they just pretended he wasn't one until one of THEM got the same treatment, I'd lean towards him not making shit up.
Further, according to Dave's own account, his mother worked pretty hard to lie about things, and based on the incredibly detailed injuries described in the book (including a gut wound that should have left a noticeable scar), he's either an amazing liar or his mother should burn in Hell for her crimes.