code: function(fieldOptions) {
        
        // Subfields should inherit required property
        if (this.options.required) {
           fieldOptions.required = true;
        }
        
        return inputEx.CombineField.superclass.renderField.call(this, fieldOptions);
     }
docs: Override to force required option on each subfield
  @param {Object} fieldOptions The field properties as required by inputEx()