public TreeCursor getFirstChild() {
        if (tree.getChildren().isEmpty()) {
            return null;
        } else {
            return new TreeCursor(tree.getChildren().get(0), this);
        }
    }
Get the first child of the wrapped tree.

@return Return the first child, or null if the tree has no children.
smithy-syntax/src/main/java/software/amazon/smithy/syntax/TreeCursor.java