I asked Mike Teskowitz this question on the following Blue Forum thread:
https://jeremybamberforum.co.uk/index.php/topic,10786.0.html
Mike answer on the thread:
Quote from: mike tesko on October 03, 2021, 06:28:18 PM
During the 11 months or so, after and during the time I spent on the same wing at HMP Full Sutton as Jeremy (in a single cell next to eachother) I have no clear recollection of him having on display in his single cell on B Wing any photographs of any of the five deceased members of his family. Although, he spoke fondly of them all regularly in my presence when we chatted about his case in his single cell...
Jeremy is supposed to have hated his parents. I have to say that, if my parents had been gunned down in their own home and I had been wrongly convicted for it, I would probably have some pictures of them on my cell wall - especially if I had no family of my own.
I appreciate that, if he is innocent, he will have had, and will still have, mixed feelings about Sheila - for perfectly obvious and understandable reasons - and he probably wouldn't be overly-emotional about his nephews, but Nevill and June were his parents and had looked after him since before he could remember anything.
One can't draw definitive conclusions but it sounds like Jeremy may not have been emotionally close to his adoptive parents. It's an easy conclusion to come to, but perhaps not surprising, for all sorts of reasons we need not labour here.
That doesn't mean he hated them, though, and it certainly doesn't mean he hated them enough to kill them. But I do not believe he could have killed them without hating them.