(defconst winny/child-widget-regex "^\\(Hide\\|Show Value\\)")

(defun winny/forward-child-widget (&optional arg)
  "Navigate to next child widget by ARG.

Use a Negative ARG to navigate backwards."
  (interactive "p")
  (when (and (looking-at winny/child-widget-regex) (> arg 0))
    (setq arg (+ 1 arg)))
  (re-search-forward winny/child-widget-regex nil nil arg)
  ;; Ensure point is at the beginning of the line.
  (move-beginning-of-line nil))

(defun winny/backward-child-widget (&optional arg)
  "Navigate to previous child widget by ARG.

Use a Negative ARG to navigate forwards."
  (interactive "p")
  (winny/forward-child-widget (- arg)))

(define-key custom-mode-map (kbd "M-n") 'winny/forward-child-widget)
(define-key custom-mode-map (kbd "M-p") 'winny/backward-child-widget)
(define-key custom-mode-map (kbd "M-RET") 'Custom-newline)