Everyone addresses Vera Miles's character as Diane Mangus. She introduces herself to Barnaby and JR as Diane Magnus.
Religious beliefs notwithstanding, no one seems to mind that John David Carson's character would have been alive when Vera Miles husband was living---as he is 25 here, so his character was 25-30---and so the whole plot makes no sense, because one has to be born after the person they're reincarnated as has already died, and for many years at that.