On WTA the hike is marked as kids friendly, but I don't think its that easy for kids. That being said, your 7 year old should be fine. There's a lot a big rocks that you will have to pass in the last half mile or so, thus he will need some help there from you, but otherwise it should be ok.
No, the Discover Pass is only for state parks. This lot requires a NW Forest Pass.
Thanks for your informtion. Is it hard for kid? My son is 7.
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