I fully believe Chloe was 'sane' and acted alone in these murders.
When a child is 'bright' or even literally of 'genius' IQ and applies themselves to science or math, or something beneficial, their intelligence is lauded. In Chloe's case, she applied it to murdering her family, getting what she wanted and getting away with it. Genius + psychopathy never ends well.
One of her kids went on to develop scientific patents for making light-emitting devices from organic cells, as well as contributions to cancer research, which suggests to me a life devoted to the betterment of humanity through science. Perhaps he shared his mother's intelligence, but not her psychopathy.
I can't imagine what sort of mother she was. Perhaps she was a good one, who knows? Another of her other sons changed his name by deed poll, however, for which there could be a dozen reasons, including hating his mother. I note two of her marriages did last a decade or more, with a gap of several years between; lots of people marry more than twice in their lifetimes. One entry I found was curious, though -- there's a description of her and one husband as 'father' and 'mother' and no apparent record at all of the child. More digging to do..
It'd be really interesting to find out what she was like as an adult. Did she 'grow out' of her capacity for murdering people in the way of her desires, or did she just get more clever at it? Perhaps she never again had the need, and applied it to other forms of destruction.
What an interesting read, momtolil. And wow - there's the guy who invented the sex offender registry, and what a sad tale he ended up with. The whole case is fascinating!