You’d be surprised how much of an effort it takes to safely descend a steep slope with poor traffic. Definitely harder going up but if you check it out on google earth you can get an idea of the grade.
Yes but there is still the fact that they all died together. The initial autopsy didn't provide clues (which they would be looking for heatstroke which has a particular signature)
It just seems really weird for all three of them to die pretty much at the same time. (the baby of course could have died hours later of exposure)
I'm still betting on some kind of toxin.
Really tragic, they seemed like a really happy family.