code: func (s SearchIndex) FindChild(ctx context.Context, entity Reference, name string) (Reference, error) {
  	req := types.FindChild{
  		This:   s.Reference(),
  		Entity: entity.Reference(),
  		Name:   name,
  	}
  
  	res, err := methods.FindChild(ctx, s.c, &req)
  	if err != nil {
  		return nil, err
  	}
  
  	if res.Returnval == nil {
  		return nil, nil
  	}
  	return NewReference(s.c, *res.Returnval), nil
  }
docs: // FindChild finds a particular child based on a managed entity name.