Age
You get tooth orders. You get these tooth orders various times in your life, depending on your age.
You get baby age tooth orders (to get your first teeth). You get child age tooth orders (to get your adult teeth). Then you get old age tooth orders (when you start losing your teeth). There are tooth orders for every age.
れい
よわい
None
Gaining and losing teeth aren't the only things dependent on age. There is also an age in which you get your first ray (れい) gun.
Decide what age you have to be to get your first ray gun, and then imagine getting it when you hit that age. Perhaps you use this ray gun on your teeth, to keep them clean. Hint: when you see the radical orders it's fairly likely the reading will be れい.