Child theme

[ladygeekgeek]

Hi folks, I'm trying to get this to work with a child theme and not having much luck. Any ideas how I can format it to work? Many thanks

Warning: scandir(): Failed to open directory: No such file or directory.

// modify the path to the icons directory
add_filter( 'acf_icon_path_suffix', 'acf_icon_path_suffix' );

function acf_icon_path_suffix( $path_suffix ) {
return 'assets/icons/';
}