diff --git a/backend/tests/Feature/ElementsEndpointTest.php b/backend/tests/Feature/ElementsEndpointTest.php
index a914dd9..329e932 100644
--- a/backend/tests/Feature/ElementsEndpointTest.php
+++ b/backend/tests/Feature/ElementsEndpointTest.php
@@ -297,6 +297,234 @@ class ElementsEndpointTest extends TestCase
         );
     }
 
+    public function testReorderChildElementsRequiresAuthentication(): void
+    {
+        $setRepository = app(SetRepository::class);
+        $elementRepository = app(ElementRepository::class);
+        $set = $this->createSet($setRepository);
+        $parentElement = $this->createElement(
+            $elementRepository,
+            $set,
+            'Baderech HaAvodah',
+            'A structured path for growth',
+            null,
+            '<p>A structured path for growth</p>',
+            null,
+            null,
+            null,
+            null,
+        );
+        $firstChildElement = $this->createElement(
+            $elementRepository,
+            $set,
+            'First child',
+            'First child description',
+            null,
+            '',
+            null,
+            null,
+            null,
+            $parentElement,
+        );
+
+        $response = $this->putJson(
+            "/api/elements/{$parentElement->getId()}/children/order",
+            [
+                'childElementIds' => [$firstChildElement->getId()],
+            ],
+        );
+
+        $response->assertUnauthorized();
+        $response->assertExactJson([
+            'error' => 'unauthenticated',
+        ]);
+    }
+
+    public function testAuthenticatedReorderChildElementsPersistsOrder(): void
+    {
+        $setRepository = app(SetRepository::class);
+        $elementRepository = app(ElementRepository::class);
+        $set = $this->createSet($setRepository);
+        $parentElement = $this->createElement(
+            $elementRepository,
+            $set,
+            'Baderech HaAvodah',
+            'A structured path for growth',
+            null,
+            '<p>A structured path for growth</p>',
+            null,
+            null,
+            null,
+            null,
+        );
+        $firstChildElement = $this->createElement(
+            $elementRepository,
+            $set,
+            'First child',
+            'First child description',
+            null,
+            '',
+            null,
+            null,
+            null,
+            $parentElement,
+        );
+        $secondChildElement = $this->createElement(
+            $elementRepository,
+            $set,
+            'Second child',
+            'Second child description',
+            null,
+            '',
+            null,
+            null,
+            null,
+            $parentElement,
+        );
+        $thirdChildElement = $this->createElement(
+            $elementRepository,
+            $set,
+            'Third child',
+            'Third child description',
+            null,
+            '',
+            null,
+            null,
+            null,
+            $parentElement,
+        );
+        $this->createSession('valid-token');
+
+        $response = $this->withCredentials()
+            ->withUnencryptedCookie('auth_token', 'valid-token')
+            ->putJson(
+                "/api/elements/{$parentElement->getId()}/children/order",
+                [
+                    'childElementIds' => [
+                        $thirdChildElement->getId(),
+                        $firstChildElement->getId(),
+                        $secondChildElement->getId(),
+                    ],
+                ],
+            );
+
+        $response->assertOk();
+        $response->assertExactJson([
+            'childElements' => [
+                [
+                    'id' => $thirdChildElement->getId(),
+                    'title' => 'Third child',
+                    'description' => 'Third child description',
+                ],
+                [
+                    'id' => $firstChildElement->getId(),
+                    'title' => 'First child',
+                    'description' => 'First child description',
+                ],
+                [
+                    'id' => $secondChildElement->getId(),
+                    'title' => 'Second child',
+                    'description' => 'Second child description',
+                ],
+            ],
+        ]);
+
+        $this->getJson("/api/elements/{$parentElement->getId()}")
+            ->assertJsonPath('childElements.0.id', $thirdChildElement->getId())
+            ->assertJsonPath('childElements.1.id', $firstChildElement->getId())
+            ->assertJsonPath(
+                'childElements.2.id',
+                $secondChildElement->getId(),
+            );
+        $this->getJson("/api/elements/{$thirdChildElement->getId()}")
+            ->assertJsonPath(
+                'siblingElements.0.id',
+                $thirdChildElement->getId(),
+            )
+            ->assertJsonPath(
+                'siblingElements.1.id',
+                $firstChildElement->getId(),
+            )
+            ->assertJsonPath(
+                'siblingElements.2.id',
+                $secondChildElement->getId(),
+            );
+    }
+
+    public function testAuthenticatedReorderRejectsNestedChildElement(): void
+    {
+        $setRepository = app(SetRepository::class);
+        $elementRepository = app(ElementRepository::class);
+        $set = $this->createSet($setRepository);
+        $parentElement = $this->createElement(
+            $elementRepository,
+            $set,
+            'Baderech HaAvodah',
+            'A structured path for growth',
+            null,
+            '<p>A structured path for growth</p>',
+            null,
+            null,
+            null,
+            null,
+        );
+        $firstChildElement = $this->createElement(
+            $elementRepository,
+            $set,
+            'First child',
+            'First child description',
+            null,
+            '',
+            null,
+            null,
+            null,
+            $parentElement,
+        );
+        $secondChildElement = $this->createElement(
+            $elementRepository,
+            $set,
+            'Second child',
+            'Second child description',
+            null,
+            '',
+            null,
+            null,
+            null,
+            $parentElement,
+        );
+        $nestedChildElement = $this->createElement(
+            $elementRepository,
+            $set,
+            'Nested child',
+            'Nested child description',
+            null,
+            '',
+            null,
+            null,
+            null,
+            $firstChildElement,
+        );
+        $this->createSession('valid-token');
+
+        $response = $this->withCredentials()
+            ->withUnencryptedCookie('auth_token', 'valid-token')
+            ->putJson(
+                "/api/elements/{$parentElement->getId()}/children/order",
+                [
+                    'childElementIds' => [
+                        $firstChildElement->getId(),
+                        $nestedChildElement->getId(),
+                        $secondChildElement->getId(),
+                    ],
+                ],
+            );
+
+        $response->assertBadRequest();
+        $response->assertExactJson([
+            'error' => 'Child order contains invalid child',
+        ]);
+    }
+
     public function testDeleteChildRequiresAuthentication(): void
     {
         $setRepository = app(SetRepository::class);
diff --git a/backend/tests/Unit/Element/UseCases/ReorderChildElementsTest.php b/backend/tests/Unit/Element/UseCases/ReorderChildElementsTest.php
new file mode 100644
index 0000000..1b4829f
--- /dev/null
+++ b/backend/tests/Unit/Element/UseCases/ReorderChildElementsTest.php
@@ -0,0 +1,237 @@
+<?php
+
+namespace Tests\Unit\Element\UseCases;
+
+use App\Element\CreateElementDto;
+use App\Element\Element;
+use App\Element\UseCases\ReorderChildElements\ReorderChildElements;
+use App\Element\UseCases\ReorderChildElements\ReorderChildElementsRequest;
+use App\Exceptions\BadRequestException;
+use App\Exceptions\NotFoundException;
+use App\Set\Set as DomainSet;
+use Tests\Fakes\FakeElementRepository;
+use Tests\TestCase;
+
+class ReorderChildElementsTest extends TestCase
+{
+    private FakeElementRepository $elementRepository;
+
+    private ReorderChildElements $reorderChildElements;
+
+    protected function setUp(): void
+    {
+        $this->elementRepository = new FakeElementRepository();
+        $this->reorderChildElements = new ReorderChildElements(
+            $this->elementRepository,
+        );
+    }
+
+    public function testReordersDirectChildElements(): void
+    {
+        $set = $this->createSet(1, 'Baderech');
+        $parentElement = $this->createElement($set, 'Parent', null);
+        $firstChildElement = $this->createElement(
+            $set,
+            'First child',
+            $parentElement,
+        );
+        $secondChildElement = $this->createElement(
+            $set,
+            'Second child',
+            $parentElement,
+        );
+        $thirdChildElement = $this->createElement(
+            $set,
+            'Third child',
+            $parentElement,
+        );
+        $this->createElement($set, 'Nested child', $firstChildElement);
+
+        $childElements = $this->reorderChildElements->execute(
+            new ReorderChildElementsRequest(
+                parentElementId: $parentElement->getId(),
+                childElementIds: [
+                    $thirdChildElement->getId(),
+                    $firstChildElement->getId(),
+                    $secondChildElement->getId(),
+                ],
+            )
+        );
+
+        $this->assertSame(
+            [
+                $thirdChildElement->getId(),
+                $firstChildElement->getId(),
+                $secondChildElement->getId(),
+            ],
+            $this->elementIds($childElements),
+        );
+        $this->assertSame(
+            [
+                $thirdChildElement->getId(),
+                $firstChildElement->getId(),
+                $secondChildElement->getId(),
+            ],
+            $this->elementIds(
+                $this->elementRepository->findByParentElement($parentElement),
+            ),
+        );
+    }
+
+    public function testThrowsWhenParentElementIsMissing(): void
+    {
+        $this->expectException(NotFoundException::class);
+        $this->expectExceptionMessage('Parent element not found');
+
+        $this->reorderChildElements->execute(
+            new ReorderChildElementsRequest(
+                parentElementId: 999,
+                childElementIds: [1, 2],
+            )
+        );
+    }
+
+    public function testThrowsWhenChildIdsAreMissing(): void
+    {
+        $this->expectException(BadRequestException::class);
+        $this->expectExceptionMessage('childElementIds is required');
+
+        $this->reorderChildElements->execute(
+            new ReorderChildElementsRequest(
+                parentElementId: 1,
+                childElementIds: null,
+            )
+        );
+    }
+
+    public function testThrowsWhenChildOrderHasDuplicates(): void
+    {
+        $set = $this->createSet(1, 'Baderech');
+        $parentElement = $this->createElement($set, 'Parent', null);
+        $firstChildElement = $this->createElement(
+            $set,
+            'First child',
+            $parentElement,
+        );
+        $secondChildElement = $this->createElement(
+            $set,
+            'Second child',
+            $parentElement,
+        );
+
+        $this->expectException(BadRequestException::class);
+        $this->expectExceptionMessage('Child order contains duplicate ids');
+
+        $this->reorderChildElements->execute(
+            new ReorderChildElementsRequest(
+                parentElementId: $parentElement->getId(),
+                childElementIds: [
+                    $firstChildElement->getId(),
+                    $firstChildElement->getId(),
+                    $secondChildElement->getId(),
+                ],
+            )
+        );
+    }
+
+    public function testThrowsWhenChildOrderHasInvalidElement(): void
+    {
+        $set = $this->createSet(1, 'Baderech');
+        $parentElement = $this->createElement($set, 'Parent', null);
+        $firstChildElement = $this->createElement(
+            $set,
+            'First child',
+            $parentElement,
+        );
+        $secondChildElement = $this->createElement(
+            $set,
+            'Second child',
+            $parentElement,
+        );
+        $nestedChildElement = $this->createElement(
+            $set,
+            'Nested child',
+            $firstChildElement,
+        );
+
+        $this->expectException(BadRequestException::class);
+        $this->expectExceptionMessage('Child order contains invalid child');
+
+        $this->reorderChildElements->execute(
+            new ReorderChildElementsRequest(
+                parentElementId: $parentElement->getId(),
+                childElementIds: [
+                    $firstChildElement->getId(),
+                    $nestedChildElement->getId(),
+                    $secondChildElement->getId(),
+                ],
+            )
+        );
+    }
+
+    public function testThrowsWhenChildOrderOmitsDirectChild(): void
+    {
+        $set = $this->createSet(1, 'Baderech');
+        $parentElement = $this->createElement($set, 'Parent', null);
+        $firstChildElement = $this->createElement(
+            $set,
+            'First child',
+            $parentElement,
+        );
+        $this->createElement($set, 'Second child', $parentElement);
+
+        $this->expectException(BadRequestException::class);
+        $this->expectExceptionMessage(
+            'Child order must include every direct child',
+        );
+
+        $this->reorderChildElements->execute(
+            new ReorderChildElementsRequest(
+                parentElementId: $parentElement->getId(),
+                childElementIds: [$firstChildElement->getId()],
+            )
+        );
+    }
+
+    private function createSet(int $id, string $name): DomainSet
+    {
+        return new DomainSet(
+            id: $id,
+            name: $name,
+            description: "$name description",
+            iconImageUrl: '/assets/baderech-icon.png',
+        );
+    }
+
+    private function createElement(
+        DomainSet $set,
+        string $title,
+        ?Element $parentElement,
+    ): Element {
+        return $this->elementRepository->create(new CreateElementDto(
+            set: $set,
+            title: $title,
+            description: "$title description",
+            iconImageUrl: null,
+            richText: '',
+            shortPdfPath: null,
+            longPdfPath: null,
+            youtubeUrl: null,
+            parentElement: $parentElement,
+        ));
+    }
+
+    /**
+     * @param Element[] $elements
+     * @return int[]
+     */
+    private function elementIds(array $elements): array
+    {
+        $elementIds = [];
+        foreach ($elements as $element) {
+            $elementIds[] = $element->getId();
+        }
+
+        return $elementIds;
+    }
+}
diff --git a/frontend/rabbi_gerzi/cypress/e2e/admin-element.cy.ts b/frontend/rabbi_gerzi/cypress/e2e/admin-element.cy.ts
index 8c1f7f3..ab70619 100644
--- a/frontend/rabbi_gerzi/cypress/e2e/admin-element.cy.ts
+++ b/frontend/rabbi_gerzi/cypress/e2e/admin-element.cy.ts
@@ -191,6 +191,46 @@ describe('admin element editing', () => {
     cy.resetDb()
   })
 
+  it('reorders child elements through admin controls', () => {
+    cy.resetDb()
+    loginAsAdmin()
+    cy.visit('/admin/element/1')
+    cy.intercept('PUT', /\/api\/elements\/1\/children\/order$/)
+      .as('reorderChildElements')
+
+    cy.contains('[data-cy="admin-child-item"]', '2. Foundations')
+      .within(() => {
+        cy.get('[data-cy="admin-move-child-up"]').click()
+      })
+    cy.wait('@reorderChildElements')
+
+    cy.get('[data-cy="admin-child-status"]')
+      .should('be.visible')
+      .and('contain.text', 'Child order saved')
+    cy.get('[data-cy="admin-child-item"]')
+      .eq(0)
+      .should('contain.text', '2. Foundations')
+    cy.get('[data-cy="admin-child-item"]')
+      .eq(1)
+      .should('contain.text', '1. Introduction')
+
+    cy.contains('header.site-header a', 'View Element').click()
+    cy.get('[data-cy="child-element-link"]')
+      .eq(0)
+      .should('contain.text', '2. Foundations')
+    cy.get('[data-cy="child-element-link"]')
+      .eq(1)
+      .should('contain.text', '1. Introduction')
+
+    cy.visit('/element/3')
+    cy.get('[data-cy="element-sibling-previous"]')
+      .should('have.attr', 'href', '/element/7')
+    cy.get('[data-cy="element-sibling-next"]')
+      .should('have.attr', 'href', '/element/2')
+
+    cy.resetDb()
+  })
+
   it('uploads icon and pdf files immediately through the UI', () => {
     cy.resetDb()
     loginAsAdmin()