How young? During summertime, answer is no
We saw many smaller children and mini dogs on the trail this morning. They should be fine.
Lots of loose gravel, good shoes a must.
If you go at 7 pm there is no direct sun, but it is well-lit until about 8:30 pm. Environment is bearable. I do it carrying no water daily and am not even winded.
It is not a difficult hike if you stay on the trails, bring water, sunscreen and maybe hats. Good shoes are essential. It will be quite warm with the sun, but you don't always have to go all the way up. My nephews did it with me and they were 14 and 11.
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