Kotaru is 17 Months Old Today!

Does height vary directly with age? Sounds like a question I may ask my Advanced Algebra students and most know, through life experience, that the answer is clearly: "no!". If the rate of growth we enjoyed during our youth continued throughout adulthood, we'd have some pretty tall people out there!
However, under three years of age, direct variation may hold. Just look at Rai and Ko. At 17 months old today, Ko is about half Rai's age. Now, take a look at the photo. Ko looks about half Rai's height, right? That's pretty scientific, if you ask me. No further data is required.
Or, is that just the camera perspective? And Ko is crouching down, too. Yes, that's it. In reality, Ko is actually catching up to Rai in height. To celebrate this birthday today, I was lucky enough to have a day off of work and took the boys to the Academy of Sciences where it's a little trickier now with Ko running off in every direction. Happy Birthday, Kotaru!