Twenty Ten child theme header image change error message: wordpress

I'm trying to change the header image width of my twenty ten child theme; when I add the following code to my child theme functions file:

if ( !function_exists( 'child_theme_setup' ) ): function child_theme_setup() { define( 'HEADER_IMAGE_WIDTH', apply_filters( 'twentyten_header_image_width', 900 )); }

I get the following error message:

Parse error: syntax error, unexpected $end in... functions.php on line 132

Here is the whole code for the child functions file:

<?php
/** Tell WordPress to run child_theme_setup()
when the 'after_setup_theme' hook is run.
*/
add_action( 'after_setup_theme', 'child_theme_setup' );

/** This function will hold our new calls and over-rides */
if ( !function_exists( 'child_theme_setup' ) ):
function child_theme_setup() {

    /*
    We want a Second Navigation Bar right at the top
    This theme uses wp_nav_menu() in two locations.
    */
    register_nav_menus( array(
        'secondary' => __( 'Top Navigation', 'twentyten' ),
    ) );

// Add support for Featured Images
if (function_exists('add_theme_support')) {
    add_theme_support('post-thumbnails');
    add_image_size('index-categories', 160, 124, true);
    add_image_size('page-single', 350, 350, true);
}

function InsertFeaturedImage($content) {

global $post;

$original_content = $content;

    if ( current_theme_supports( 'post-thumbnails' ) ) {

        if ((is_page()) || (is_single())) {
            $content = the_post_thumbnail('page-single');
            $content .= $original_content;
            } else {
            $content = the_post_thumbnail('index-categories');
            $content .= $original_content;
        }

    }
    return $content;
}

add_filter( 'the_content', 'InsertFeaturedImage' );

// End Add support for Featured Images

    /* Remove the Twenty Ten registered sidebars */
    remove_action( 'widgets_init', 'twentyten_widgets_init' );

    /** Add our Widgetized Areas */
    function child_widgets_init() {

        // Load our Widget Area Names and ID's into an Array
        $widgets = array (
            array(
                "name" => "Sidebar Left One",
                "id" => "sidebar-left-one"),
            array(
                "name" => "Sidebar Left Two",
                "id" => "sidebar-left-two"),
            array(
                "name" => "Content Top",
                "id" => "content-top"),
            array(
                "name" => "Content Left",
                "id" => "content-left"),
            array(
                "name" => "Content Right",
                "id" => "content-right"),
            array(
                "name" => "Content Bottom",
                "id" => "content-bottom"),
            array(
                "name" => "Sidebar Right One",
                "id" => "sidebar-right-one"),
            array(
                "name" => "Sidebar Right Two",
                "id" => "sidebar-right-two"),
            array(
                "name" => "First Footer Widget",
                "id" => 'first-footer-widget-area'),
            array(
                "name" => "Second Footer Widget",
                "id" => 'second-footer-widget-area'),
            array(
                "name" => "Third Footer Widget",
                "id" => 'third-footer-widget-area'),
            array(
                "name" => "Fourth Footer Widget",
                "id" => 'fourth-footer-widget-area')
        );

        /* Loop through the array and add our Widgetised areas */
        foreach ($widgets as $widget) {
            register_sidebar( array(
                'name' => __( $widget['name'], 'twentyten' ),
                'id' => $widget['id'],
                'description' => __( $widget['name'] .' Area', 'twentyten' ),
                'before_widget' => '<li id="%1$s" class="widget-container %2$s">',
                'after_widget' => '</li>',
                'before_title' => '<h3 class="widget-title">',
                'after_title' => '</h3>',
            ) );
        }

    }
    /* Register sidebars by running twentyten_widgets_init() on the widgets_init hook. */
    add_action( 'widgets_init', 'child_widgets_init' );
}

/* This gets rid of the pagenavi css in your hea开发者_Go百科der */
add_action( 'wp_print_styles', 'my_deregister_styles', 100 );

function my_deregister_styles() {
    wp_deregister_style( 'wp-pagenavi' );
}

/* Changes header image size */
add_action( 'after_setup_theme', 'child_theme_setup' );

if ( !function_exists( 'child_theme_setup' ) ):
function child_theme_setup() {
    define( 'HEADER_IMAGE_WIDTH', apply_filters( 'twentyten_header_image_width', 900 ));
}

endif;

I'm not sure what is ending incorrectly as it seems to work fine before I add the header code. I've tried entering the header code in different places and in different ways, to no avail.

I see two if (...): statements, but just one endif; Could that be the problem?