Some people will lean on your fence just to see if it’s real. Stay standing, not shouting.

A limit gets tested, sometimes deliberately and sometimes with no thought behind it at all. The test is usually not an attack, it is a question about whether the thing is genuine, and the answer comes from what you do rather than from how forcefully you say it. Volume suggests uncertainty, while quiet consistency does not.

When someone pushes, restate the same thing in the same tone and add no heat to it. Let your behaviour supply the evidence. Repeating yourself calmly a few times settles it more thoroughly than one loud occasion ever would.