protected function loadRelation(array $results, string $name, Closure $constraints) : array
    {
        // First we will "back up" the existing where conditions on the query so we can
        // add our eager constraints. Then we will merge the wheres that were on the
        // query back to it in order that any where conditions might be specified.
        $relation = $this->getRelation($name);

        $relation->addEagerConstraints($results);

        call_user_func($constraints, $relation);

        // Once we have the results, we just match those back up to their parent models
        // using the relationship instance. Then we just return the finished arrays
        // of models which have been eagerly hydrated and are readied for return.
        return $relation->match($results, $name);
    }