You cannot even get Sheila from her bedroom to her parents room, without her either seeing June or her children or both your scenario is hopeless.
No wonder Cc had JB banging saucepans outside the bedroom to draw Nevil out!
Well there are 3 options -
Through the main bedroom door. In the dark.
Via the box room. In the dark.
Sheila woke & got up. Killed where Bamber found her.
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I did post this yesterday.
You need to address your 53 flaws & 47 maybe's. CSI don't make decisions on flaws & maybe's.
I don't agree Bamber banged saucepans. Cambridge will have to reply to that.