diff --git a/question/category.php b/question/category.php
index c740522a63a2a..952d4315a00cb 100644
--- a/question/category.php
+++ b/question/category.php
@@ -97,7 +97,7 @@
     }
 
     question_remove_stale_questions_from_category($param->delete);
-    $questionstomove = $DB->count_records("question", array("category" => $param->delete));
+    $questionstomove = count($qcobject->get_real_question_ids_in_category($param->delete));
 
     // Second pass, if we still have questions to move, setup the form.
     if ($questionstomove) {
diff --git a/question/category_class.php b/question/category_class.php
index 1713cadea5cf7..61123d7c89fea 100644
--- a/question/category_class.php
+++ b/question/category_class.php
@@ -435,10 +435,8 @@ public function display_move_form($questionsincategory, $category){
     }
 
     public function move_questions($oldcat, $newcat){
-        global $DB;
-        $questionids = $DB->get_records_select_menu('question',
-                'category = ? AND (parent = 0 OR parent = id)', array($oldcat), '', 'id,1');
-        question_move_questions_to_category(array_keys($questionids), $newcat);
+        $questionids = $this->get_real_question_ids_in_category($oldcat);
+        question_move_questions_to_category($questionids, $newcat);
     }
 
     /**
@@ -606,4 +604,21 @@ public function update_category($updateid, $newparent, $newname, $newinfo, $newi
             redirect($this->pageurl); // Always redirect after successful action.
         }
     }
+
+    /**
+     * Returns ids of the question in the given question category.
+     *
+     * This method only returns the real question. It does not include
+     * subquestions of question types like multianswer.
+     *
+     * @param int $categoryid id of the category.
+     * @return int[] array of question ids.
+     */
+    public function get_real_question_ids_in_category(int $categoryid): array {
+        global $DB;
+        $select = 'category = :categoryid AND (parent = 0 OR parent = id)';
+        $params = ['categoryid' => $categoryid];
+        $questionids = $DB->get_records_select('question', $select, $params);
+        return array_keys($questionids);
+    }
 }
diff --git a/question/tests/behat/question_categories.feature b/question/tests/behat/question_categories.feature
index fbcba7531f1c6..cb792938fb19a 100644
--- a/question/tests/behat/question_categories.feature
+++ b/question/tests/behat/question_categories.feature
@@ -86,3 +86,20 @@ Feature: A teacher can put questions in categories in the question bank
     And the field "Select a category" matches value "      Subcategory (1)"
     And the "Select a category" select box should contain "Used category"
     And the "Select a category" select box should not contain "Used category (1)"
+
+  @_file_upload
+  Scenario: Multi answer questions with their child questions can be moved to another category when the current category is deleted
+    When I navigate to "Question bank > Import" in current page administration
+    And I set the field "id_format_xml" to "1"
+    And I upload "question/format/xml/tests/fixtures/multianswer.xml" file to "Import" filemanager
+    And I press "id_submitbutton"
+    And I press "Continue"
+    And I am on "Course 1" course homepage
+    And I navigate to "Question bank > Categories" in current page administration
+    And I click on "Delete" "link" in the "Default for Test images in backup" "list_item"
+    And I should see "The category 'Default for Test images in backup' contains 1 questions"
+    And I select "Used category" from the "Category" singleselect
+    And I press "Save in category"
+    Then I should not see "Default for Test images in backup"
+    And I follow "Add category"
+    And I should see "Used category (2)"
diff --git a/question/tests/category_class_test.php b/question/tests/category_class_test.php
index adbe41cea3af5..e5931a72d11af 100644
--- a/question/tests/category_class_test.php
+++ b/question/tests/category_class_test.php
@@ -175,4 +175,68 @@ public function test_update_category_try_to_set_duplicate_idnumber() {
         $this->assertSame('New name', $newcat->name);
         $this->assertNull($newcat->idnumber);
     }
+
+    /**
+     * Test that get_real_question_ids_in_category() returns question id
+     * of a shortanswer question in a category.
+     *
+     * @covers ::get_real_question_ids_in_category
+     */
+    public function test_get_real_question_ids_in_category_shortanswer() {
+        $generator = $this->getDataGenerator()->get_plugin_generator('core_question');
+        $categoryid = $this->topcat->id;
+
+        // Short answer question is made of one question.
+        $shortanswer = $generator->create_question('shortanswer', null, ['category' => $categoryid]);
+        $questionids = $this->qcobject->get_real_question_ids_in_category($categoryid);
+        $this->assertCount(1, $questionids);
+        $this->assertContains($shortanswer->id, $questionids);
+    }
+
+    /**
+     * Test that get_real_question_ids_in_category() returns question id
+     * of a multianswer question in a category.
+     *
+     * @covers ::get_real_question_ids_in_category
+     */
+    public function test_get_real_question_ids_in_category_multianswer() {
+        global $DB;
+        $countq = $DB->count_records('question');
+
+        $generator = $this->getDataGenerator()->get_plugin_generator('core_question');
+        $categoryid = $this->topcat->id;
+
+        // Multi answer question is made of one parent and two child questions.
+        $multianswer = $generator->create_question('multianswer', null, ['category' => $categoryid]);
+        $questionids = $this->qcobject->get_real_question_ids_in_category($categoryid);
+        $this->assertCount(1, $questionids);
+        $this->assertContains($multianswer->id, $questionids);
+        $this->assertEquals(3, $DB->count_records('question') - $countq);
+    }
+
+    /**
+     * Test that get_real_question_ids_in_category() returns question id
+     * of a multianswer question in a category even if their child questions are
+     * linked to a category that doesn't exist.
+     *
+     * @covers ::get_real_question_ids_in_category
+     */
+    public function test_get_real_question_ids_in_category_multianswer_bad_data() {
+        global $DB;
+        $countq = $DB->count_records('question');
+
+        $generator = $this->getDataGenerator()->get_plugin_generator('core_question');
+        $categoryid = $this->topcat->id;
+
+        // Multi answer question is made of one parent and two child questions.
+        $multianswer = $generator->create_question('multianswer', null, ['category' => $categoryid]);
+
+        // Update category id for child questions to a category that doesn't exist.
+        $DB->set_field_select('question', 'category', 123456, 'id <> :id', ['id' => $multianswer->id]);
+
+        $questionids = $this->qcobject->get_real_question_ids_in_category($categoryid);
+        $this->assertCount(1, $questionids);
+        $this->assertContains($multianswer->id, $questionids);
+        $this->assertEquals(3, $DB->count_records('question') - $countq);
+    }
 }