I have a tricky situation so hoping people can suggest a solution to minimise the impact.
My one kid has ADHD and one is just 3.5 years old. When this kid with ADHD is upset, he tends to throw things and becomes out of control. This has resulted in various stuff flying over the fence. This includes the pebbles, plastic toys, hot wheels, plastic bat, basket ball and hand ball.
Poor neighbour has raised a complaint few times as there is risk of human injury, property damage and also harm to his pet.
I have explained the consequences to my kids but I think little one is too young to appreciate the situation. The other kid becomes agitated from time to time because of his medical condition.
We can't continue to allow them screen time for majority of the day as it's also not beneficial and they also need to play outdoor for their own benefit. Due to busy work schedule, we can't monitor them at all times as well. It takes just couple of seconds for stuff to cross the fence even if we are monitoring :(
Finally school holidays doesn't help either.
Install netting above fence
Monitor your own child during outdoor
Keep them indoor if you can't keep them in check
If you're your neighbor, would you tolerate your neighbor's kids throwing stuffs over fence whilst your kids were playing outside ?
It's not beneficial for them to keep their kids indoor just because neighbor's kids throwing stuffs over fence and their kids need to play outdoor for their own benefit too. Not just caring your own benefit. Entitled much.
And like you, they also can't monitor the fence for any stuffs flying over anytime trying to catch them to protect their kids in their own backyard.