If this item has a name (i.e. extends
ApiNameMixin), then return all items that have the same parent and the same name. Otherwise, return all items that have the same parent and the same
Examples: For a function, this would return all overloads for the function. For a constructor, this would return all overloads for the constructor. For a merged declaration (e.g. a
enum with the same name), this would return both declarations. If this item does not have a parent, or if it is the only item of its name/kind, then the result is an array containing only this item.