@Test
public void listChildren() throws Exception {

    PerPage root = createPage(null, "root");
    PerPage child = createPage(root, "child");
    PerPage child1 = createPage(child, "child-1");
    PerPage child2 = createPage(child, "child-2");
    assertEquals("Only expected one child of root", 1, countIterable(root.listChildren()));
    assertEquals("Only expected two grand children of child", 2, countIterable(child.listChildren()));
    assertEquals("Did not expected any children of grand child 1", 0, countIterable(child1.listChildren()));
    assertEquals("Did not expected any children of grand child 2", 0, countIterable(child2.listChildren()));
}