Ask yourself who was Ralph referring to, if he told Jeremy, " She has got the gun, she has gone crazy, come quickly"...
Ralph was dead by that stage,shot eight times and bashed over the head,fracturing his jaw with damage to teeth,neck and larynx. The left side of his lip was wounded,he had black eyes,a broken nose,bruising to cheeks, a cut lip,cuts on the head,bruising to the right forearm and circular burn-type marks on his back.He had been shot six times to the head and face,fired when a rifle was a few inches away from his skin. The remaining shots had occurred when he was at least two feet away.Based on where the empty cartridges were found-three were in the kitchen and one on the stairs-the Police concluded he had been shot four times upstairs,but had managed to get downstairs where a struggle took place,during which he was hit several times with the rifle and shot again,this time fatally.
The description of Ralph's injuries I have taken from Wikipedia-The White House Farm Murders. You have to ask yourself why Ralph(Nevill) in this life and death situation meekly surrenders the telephone to Sheila without giving one last yell down the receiver to Jeremy. Jeremy tells Police that "my father sounded terrified when he called" yet has the time to flick unconcernedly through the Yellow Pages for ten minutes,yet when he does finally get round to making contact with the Police he is the first to hasten them. Sheila herself it seems has reloaded a gun twice with two magazines,necessitating trips up and downstairs as she can't store ammunition on her person,her nails are undamaged,there is no gun oil on her nightdress or lead residue on her hands. Her left hand is blood-free,yet she is supposed to have been in contact with at least one other person and shot herself twice,or if it's your cup of tea,been shot by the Police.