Rotating images in child theme

I’m using wp 3.3.1 and making a child theme of the suffusion theme.

I want to add rotating images to the widget area in the header. I added this function to the child them

<?php
add_action( 'after_setup_theme', 'child_theme_setup' );
if ( ! function_exists('child_theme_setup') ):
function child_theme_setup() {
add_theme_support( 'post-thumbnails' );
define( 'HEADER_TEXTCOLOR', '' );
define( 'HEADER_IMAGE', '%s/images/headers/flex.jpg' );
define( 'HEADER_IMAGE_WIDTH', apply_filters( 'child_theme_header_image_width', 458 ) );
define( 'HEADER_IMAGE_HEIGHT', apply_filters( 'child_theme_header_image_height', 155 ) );
set_post_thumbnail_size( HEADER_IMAGE_WIDTH, HEADER_IMAGE_HEIGHT, true );
define( 'NO_HEADER_TEXT', true );
add_custom_image_header( '', 'child_theme_admin_header_style' );
// Custom header images
register_default_headers( array (
'flex' => array (
'url' => '%s/images/headers/flex.jpg',
'thumbnail_url' => '%s/images/headers/flex-thumbnail.jpg',
'description' => __( 'Flex', '' )
),
'pushup' => array (
'url' => '%s/images/headers/pushup.jpg',
'thumbnail_url' => '%s/images/headers/pushup-thumbnail.jpg',
'description' => __( 'Pushup', '' )
),
'stretch' => array (
'url' => '%s/images/headers/stretch.jpg',
'thumbnail_url' => '%s/images/headers/stretch-thumbnail.jpg',
'description' => __( 'Stretch', '' )
),
'closeup' => array (
'url' => '%s/images/headers/closeup.jpg',
'thumbnail_url' => '%s/images/headers/closeup-thumbnail.jpg',
'description' => __( 'Closeup', '' )
),
'side' => array (
'url' => '%s/images/headers/side.jpg',
'thumbnail_url' => '%s/images/headers/side-thumbnail.jpg',
'description' => __( 'Side', '' )
),
'workout' => array (
'url' => '%s/images/headers/workout.jpg',
'thumbnail_url' => '%s/images/headers/workout-thumbnail.jpg',
'description' => __( 'Workout', '' )
),
'jump' => array (
'url' => '%s/images/headers/jump.jpg',
'thumbnail_url' => '%s/images/headers/jump-thumbnail.jpg',
'description' => __( 'Jump', '' )
),
'red' => array (
'url' => '%s/images/headers/red.jpg',
'thumbnail_url' => '%s/images/headers/red-thumbnail.jpg',
'description' => __( 'Red', '' )
),
'ladies' => array (
'url' => '%s/images/headers/ladies.jpg',
'thumbnail_url' => '%s/images/headers/ladies-thumbnail.jpg',
'description' => __( 'Ladies', '' )
)
) );
}
endif;
if ( ! function_exists( 'child_theme_admin_header_style' ) ) :
function child_theme_admin_header_style() {
?>
<style type="text/css">
#headimg {
height: <?php echo HEADER_IMAGE_HEIGHT; ?>px;
width: <?php echo HEADER_IMAGE_WIDTH; ?>px;
}
#headimg h1, #headimg #desc {
display: none;
}
</style>
<?php
}
endif;
?>

Added this code to the widget in the header

<?php
// Check if this is a post or page, if it has a thumbnail, and if it's a big one
if ( is_singular() &&
has_post_thumbnail( $post->ID ) &&
( /* $src, $width, $height */ $image = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), 'post-thumbnail') ) &&
$image[1] >= HEADER_IMAGE_WIDTH ) :
// We have a new header image!
echo get_the_post_thumbnail( $post->ID, 'post-thumbnail' );
else : ?>
<img src="<?php header_image(); ?>" width="<?php echo HEADER_IMAGE_WIDTH; ?>" height="<?php echo HEADER_IMAGE_HEIGHT; ?>" alt="" />
<?php endif; ?>

All the images are located in a sub folder of the images folder of the child theme.

The images do not display unless I move the images sub folder to the parent theme.

What do I need to change to get the images to display from the child theme instead of the parent theme?