I agree that most 4 year olds won't need them - but I'd bring one along anyway. There are 3 year olds who do need them so I could understand a few 4 year olds needing them. My first child was a runner and barely 3 when we took him to Disney the first time. We made him wear it the first day since he was the type to sprint off with wild abandon at that age. He didn't want to wear it the second day, so we told him that if he stayed near us, that we wouldn't make him wear it. He knew that the second he wandered off, he was getting the harness on him. It was a great way to force him to stay near us and he actually surprised us and did quite well! So I'd take one and let the kids know you have it - and you're not afraid of using it! It's a nice natural consequence and may encourage them to not wander off.
My second child always stayed right by my side, so there was no need to take a harness at all with her. If there's any chance you may have a runner, bring one so you have a plan B.
My second child always stayed right by my side, so there was no need to take a harness at all with her. If there's any chance you may have a runner, bring one so you have a plan B.


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