Child theme language files

I’m making a child theme and I was wondering if I created the language file correctly. I took the parent theme’s .po and I merged it with the .po file of the child theme so it looks something like this:

#: parent/index.php:161
msgid "Read more"
msgstr ""

#: child/header.php:73
msgid "Welcome!"
msgstr ""

I placed the new .po file in my child themes languages folder. This is code that is in the parent theme to load the language file:

// Make theme available for translation
	// Translations can be filed in the /languages/ directory
	load_theme_textdomain(PW_THEME_FILE, TEMPLATEPATH . '/languages');

	$locale = get_locale();
	$locale_file = TEMPLATEPATH . "/languages/$locale.php";
	if ( is_readable( $locale_file ) )
		require_once( $locale_file );

Should I copy that code into the child theme’s functions.php file or do I need to use the load_child_theme_textdomain() function?

Any help would be appreciated.