code: public function children($node) {
      $query = $this->node->newQuery();
  
      $query->where($this->node->getQualifiedParentColumnName(), '=', $node->getKey());
  
      // We must also add the scoped column values to the query to compute valid
      // left and right indexes.
      foreach($this->scopedAttributes($node) as $fld => $value)
        $query->where($this->qualify($fld), '=', $value);
  
      $query->orderBy($this->node->getQualifiedLeftColumnName());
      $query->orderBy($this->node->getQualifiedRightColumnName());
      $query->orderBy($this->node->getQualifiedKeyName());
  
      return $query->get();
    }
docs: Return all children for the specified node.
  
  @param   Baum\Node $node
  @return  Illuminate\Database\Eloquent\Collection