Thank goodness, children do grow up! When they get to be old enough, make it a requirement of your helping with college $$, that they have to do the thru-hike with you. Moreover, have the kids carry most the weight (after all look at how many hours you hauled them around!). My daughter "worked" for some of her college money by backpacking with me, however poor old Mom carried more weight!

I bet at your age, you can do some long-term planning to take a leave-of-absense. Shoot- get a sponsor and give "mileage money" to charity. Waiting until 65-67 may be too late. I would aim to do it in your 50's. Where there is a will, there is a way!