Catchable fatal error: Object of class WP_Error could not be converted to string

this is the code from line 117 to 123

<?php // get parent category
                                $category = get_the_category();
                                $cat_tree = get_category_parents($category[0]->term_id, FALSE, ':', TRUE);
                                $top_cat = split(':',$cat_tree);
                                $parentObj = get_category_by_slug($top_cat[0]);
                                $parent = $parentObj->name;
                                ?>

Just to verify, which line is 120?

this is line 120
$top_cat = split(':',$cat_tree);

Your query may be better resolved in the ‘How to’ or ‘Themes’ forum.

thanks a lot, i appreciate

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