protected function _mergeProperty($property, $parentClasses, $options)
    {
        $thisValue = $this->{$property};
        $isAssoc = false;
        if (isset($options['associative']) &&
            in_array($property, (array)$options['associative'])
        ) {
            $isAssoc = true;
        }

        if ($isAssoc) {
            $thisValue = Hash::normalize($thisValue);
        }
        foreach ($parentClasses as $class) {
            $parentProperties = get_class_vars($class);
            if (empty($parentProperties[$property])) {
                continue;
            }
            $parentProperty = $parentProperties[$property];
            if (!is_array($parentProperty)) {
                continue;
            }
            $thisValue = $this->_mergePropertyData($thisValue, $parentProperty, $isAssoc);
        }
        $this->{$property} = $thisValue;
    }