protected function checkRelationExistence($name)
    {
        $getter = 'get' . ucfirst($name);
        $class = get_class($this->owner);

        if (method_exists($this->owner, $getter)) {
            /** @var ActiveQuery $value */
            $value = $this->owner->$getter();

            if (!($value instanceof ActiveQueryInterface)) {
                throw new InvalidConfigException("Value of relation '$getter' not valid");
            }

            $this->models[$name]['multiple'] = $value->multiple;
        } else {
            throw new InvalidConfigException("Relation '$class::$getter' for attribute '$name' does not exists");
        }
    }