This should really only be an issue when the children of an element are all the same type of element and are at the same depth level. For example, this is very common for li elements in a ul element.<p>We try to keep the structure of the html so that wrappers generally keep different UI components separate from each other. In other cases, like in the example in the blog post, we just use the index from the .map() loop to add a key to every element we know will need one. React should also warn you when this is an issue.