We're comfortable saying to a fifteen-year-old, "My, how you've grown?" But we don't say that to a sixty-five-year-old, mainly because we're fixated on physical, not personal growth. And, of course, we will never say to that fifteen-year-old, "Wow, you've aged since I last saw you."

I sort of hate this question because it suggests growing and aging are not simultaneous, but I'll ask it anyway:

What's the precise age when most people tend to notice someone's aging more than their growing? Is it 25, 45, 65, never?