Pause for a moment, How tall are you now?
Many families keep a record of their kids growth by marking height on a door jamb somewhere. This is a version of that that doesn’t make a permanent record, but it will probably make a permanent memory for your child.
Have your kids stand next to you and measure where they come up to on your body. They likely will be excited to see how tall they’re getting. Do you think they’ll eventually be taller than you? Will your middle son outgrow his older brother one day? It’s great fun to speculate about this with your kids.
I actually remember doing this with my mom. I think it was exciting because as kids we often see our parents as the “ultimate” grown up. For what it’s worth I never got taller than my mom, and my grandmother is even taller than her. We’re shrinking by the generation!