How old is your son? How heavy? How tall? I ask because if you are willing to use bike friendly trails there are many forms of ADA accessible ways to do it - where you would push him. (Consider this - you can get jogger strollers rated to 75 lbs and up!)

Also, search online for 4WheelBob and what he has done - he is in a wheelchair and goes many crazy places in CA. smile

Also...since his balance is a serious area - my suggestion is no backpack for him. None. Does he use trekking poles for any help?
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