Kids and fences !
Like Santa Claus they are resurrected every year.
1. Do not fall out with kids , they are like midges ;ie persistant.
2. Do not fallout with parents , they figure Johnny is grand and you are a grumpy git.
3. Avoid signs , nothing like them to prove point 2.
The (quiet) application of sticky paint should work. It is your fence after all .
The Dark Winter evenings should deter them.
And yes , kids grow up but some of their parents refuse to forgive perceived grumpiness.Don,t fall out with neighbours.
Good Luck.