Rob Donovan: A killer walking the cobbles

Corrie fan /fiction story. Rob Donovan has made the worst mistake of his life, killing Tina McIntyre to stop her from blowing Peter & her affair to Rob's brother, Carla. But when he soon realises Carla already knows & storms round to Tina's flat only to be the one to find her lying unconscious & heavily beaten. Will Rob let everyone believe it was Carla & let her be sent down? Or will he hatch a plan to convince the police that Peter did it?! Or will he be rumbled & found guilty for not only Tina's, but Carla's murder! ( Note some events in this story occurred in the TV series )