One is, of course, other things besides grandparent: husband, brother, neighbor, library patron, tourist, driver, customer, patient, concerned citizen, angry opponent of power lines and highways, rider of a bicycle, airline passenger, and so on. Few of these roles are either attained or denied one on the basis of age. You have to meet age qualifications to vote, buy alcohol, or attain a driver’s license (and in many states demonstrate your competence to keep it past a certain age). But a great many social roles are, in principle at least, not age-specific. Boarding an airplane doesn’t particularly require you to “act your age,” although being over 75 does get you past the TSA agent without removing your shoes. I know how to use the self-checkout lane at the supermarket, thank you very much, I have opinions about road construction that I will gladly and perhaps too emphatically share at a public meeting, and I stare at my IPhone as much as any millennial. White hair and liver spots are irrelevant.