public function remove($key, Model $model)
    {
        if (false === $this->isHasMany($key)) {
            return $this;
        }
        if (true === $this->isInverse($key)) {
            throw ModelException::cannotModifyInverse($this, $key);
        }
        $this->touch();
        $collection = $this->hasManyRelationships->get($key);
        $collection->remove($model);
        $this->doDirtyCheck();
        return $this;
    }