Ohioguy wrote:
....
... put[ting] ... rock on top of the landscape fabric, ...

....
I'm not sure if it is partly due to the neighbor kid playing on the
stones, the mailman walking on them, or the increased slope. All I know
for sure is that the stones are coming loose on the steepest part, about
a 3' tall by 5' wide section, and moving down onto my neighbor's parking
....
I've been trying to think of different ways to successfully solve this
problem. ...

What about lawn divider/edging strips across the width every so often to
contain the rock in various smaller sections...

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