diff --git src/wp-admin/edit-form-advanced.php src/wp-admin/edit-form-advanced.php
index 392b514..1627439 100644
--- src/wp-admin/edit-form-advanced.php
+++ src/wp-admin/edit-form-advanced.php
@@ -259,7 +259,7 @@ foreach ( get_object_taxonomies( $post ) as $tax_name ) {
 	add_meta_box( $tax_meta_box_id, $label, $taxonomy->meta_box_cb, null, 'side', 'core', array( 'taxonomy' => $tax_name ) );
 }
 
-if ( post_type_supports( $post_type, 'page-attributes' ) || count( get_page_templates( null, $post_type ) ) > 0 ) {
+if ( post_type_supports( $post_type, 'page-attributes' ) || count( get_page_templates( $post ) ) > 0 ) {
 	add_meta_box( 'pageparentdiv', $post_type_object->labels->attributes, 'page_attributes_meta_box', null, 'side', 'core' );
 }
 
diff --git src/wp-includes/class-wp-theme.php src/wp-includes/class-wp-theme.php
index 66f623e..8b3661a 100644
--- src/wp-includes/class-wp-theme.php
+++ src/wp-includes/class-wp-theme.php
@@ -1082,7 +1082,7 @@ final class WP_Theme implements ArrayAccess {
 		$post_templates = isset( $post_templates[ $post_type ] ) ? $post_templates[ $post_type ] : array();
 
 		if ( $this->parent() ) {
-			$post_templates += $this->parent()->get_page_templates( $post );
+			$post_templates += $this->parent()->get_page_templates( $post, $post_type );
 		}
 
 		/**
diff --git tests/phpunit/data/themedir1/page-templates-child/style.css tests/phpunit/data/themedir1/page-templates-child/style.css
new file mode 100644
index 0000000..2b54037
--- /dev/null
+++ tests/phpunit/data/themedir1/page-templates-child/style.css
@@ -0,0 +1,12 @@
+/*
+Theme Name: Page Template Child Theme
+Theme URI: http://example.org/
+Description: An example child theme with page templates
+Version: 0.1
+Author: Mr. WordPress
+Author URI: http://wordpress.org/
+Template: page-templates
+
+This is just a stub to test the loading of the above metadata.
+
+*/
diff --git tests/phpunit/tests/admin/includesTheme.php tests/phpunit/tests/admin/includesTheme.php
index ba76bf1..5319006 100644
--- tests/phpunit/tests/admin/includesTheme.php
+++ tests/phpunit/tests/admin/includesTheme.php
@@ -85,4 +85,29 @@ class Tests_Admin_includesTheme extends WP_UnitTestCase {
 		), get_page_templates( null, 'post' ) );
 		$this->assertEquals( array(), get_page_templates( null, 'bar' ) );
 	}
+
+	/**
+	 * @ticket 38696
+	 */
+	function test_page_templates_child_theme() {
+		$theme = wp_get_theme( 'page-templates-child' );
+		$this->assertNotEmpty( $theme );
+
+		switch_theme( $theme['Template'], $theme['Stylesheet'] );
+
+		$this->assertEqualSetsWithIndex( array(
+			'Top Level' => 'template-top-level-post-types.php',
+			'Sub Dir'   => 'subdir/template-sub-dir-post-types.php',
+		), get_page_templates( null, 'foo' ) );
+		$this->assertEqualSetsWithIndex( array(
+			'Top Level' => 'template-top-level-post-types.php',
+			'Sub Dir'   => 'subdir/template-sub-dir-post-types.php',
+		), get_page_templates( null, 'post' ) );
+		$this->assertEqualSetsWithIndex( array(
+			'Top Level'                           => 'template-top-level.php',
+			'Sub Dir'                             => 'subdir/template-sub-dir.php',
+			'This Template Header Is On One Line' => 'template-header.php',
+		), get_page_templates() );
+		$this->assertEquals( array(), get_page_templates( null, 'bar' ) );
+	}
 }