code: public function findFor($name, $model)
      {
          if (method_exists($model, 'get' . $name)) {
              $method = new \ReflectionMethod($model, 'get' . $name);
              $realName = lcfirst(substr($method->getName(), 3));
              if ($realName !== $name) {
                  throw new InvalidArgumentException('Relation names are case sensitive. ' . get_class($model) . " has a relation named \"$realName\" instead of \"$name\".");
              }
          }
  
          return $this->multiple ? $this->all() : $this->one();
      }
docs: Finds the related records for the specified primary record.
  This method is invoked when a relation of an ActiveRecord is being accessed in a lazy fashion.
  @param string $name the relation name
  @param ActiveRecordInterface|BaseActiveRecord $model the primary model
  @return mixed the related record(s)
  @throws InvalidArgumentException if the relation is invalid