Problem with the functions-php in child-theme

Hi,
at first thanks for this great theme. I love it.

But I have a problem with the functions-php in my child-theme. I want to have the following modifications. The code I use is:

<?php

/* ————————————————————————————————————————–
Thumbnails
/* ————————————————————————————————————————–*/

$avia_config[‘imgSize’][‘widget’] = array(‘width’=>80, ‘height’=>80);
$avia_config[‘imgSize’][‘square’] = array(‘width’=>300, ‘height’=>300);
$avia_config[‘imgSize’][‘square_small’] = array(‘width’=>180, ‘height’=>180);
$avia_config[‘imgSize’][‘gallery’] = array(‘width’=>450, ‘height’=> 300);
$avia_config[‘imgSize’][‘singlepic’] = array(‘width’=>600, ‘height’=>600 , ‘crop’ => false);
$avia_config[‘imgSize’][‘masonry’] = array(‘width’=>377, ‘height’=>377 , ‘crop’ => false);
$avia_config[‘imgSize’][‘entry_with_sidebar’] = array(‘width’=>1000, ‘height’=>450);

/* ————————————————————————————————————————–
Sidebar
/* ————————————————————————————————————————–*/

$avia_config[‘layout’][‘fullsize’] = array(‘content’ => ‘twelve alpha’, ‘sidebar’ => ‘hidden’, ‘meta’ => ‘two alpha’, ‘entry’ => ‘eleven’);
$avia_config[‘layout’][‘sidebar_left’] = array(‘content’ => ‘ten’, ‘sidebar’ => ‘two alpha’ ,’meta’ => ‘two alpha’, ‘entry’ => ‘ten’);
$avia_config[‘layout’][‘sidebar_right’] = array(‘content’ => ‘ten alpha’, ‘sidebar’ => ‘two alpha’, ‘meta’ => ‘two alpha’, ‘entry’ => ‘ten alpha’);

/* ————————————————————————————————————————–
* Tiled Mosaic
/* ————————————————————————————————————————–*/

if ( ! isset( $content_width ) )
$content_width = 800;

And now my problem. It works fine, if I change the file in the parent-theme, but if I use this code as a functions.php in my child-theme, I get a blank page in my browser each time. So I have to overwrite the file again and again whith ervery update oft the parent theme.

Do you have any idea about this error?

Kind regards
Cora