Hello everyone, I'm hoping you guys can help me with this error. Here's what I'm getting: Notice: Undefined variable: children in L:\localhost\catalog\catalog_0.1.0\includes\classes\tree.class.php on line 58 This error occurs only when the class's method outputs $children as having a value of zero. Below is the class. I want it to return zero but I don't want this error. Do I need to change my error settings in my php.ini file? The error level is currently set to E_ALL and I'm using PHP 5.0.1. If at all possible, I want to keep this error setting at high because I want everything to be coded strictly. What did I do wrong in my class and how can I fix it to where it doesn't output an error when a class's method returns a value of zero? Here's the class: function get_children($parent) { $parent_coord = tree::get_item_coord($parent); $descendants = $this->get_descendants($parent); for ($i = 0; $i < count($descendants); $i++) { if ((empty($children)) && (($parent_coord['0']['lft'] + 1) == $descendants[$i]['lft'])) { $children[] = $descendants[$i]; // found first child } elseif (($children[count($children)-1]['rgt'] + 1 == $descendants[$i]['lft']) && $children[count($children)-1]['rgt'] + 1 != $parent_coord['0']['rgt']) { $children[] = $descendants[$i]; // find next children } } return $children; } Thanks in advance to anyone that can explain this error to me. Nilaab