Zachary Davis killed his mum and tried to set his brother on fire - but later claimed he did't do it - and it was the fault of his sibling.

We all went to school with at least one weirdo... but did any of your former classmates bludgeon their mum to death with a sledgehammer...

The teen tells Dr. Phil how he bludgeoned his mum to death with a sledgehammer as she slept... you won't be able to un-see this!