Baby Got Back?

I have been recently frustrated by some of my son's clothes.  He is wearing a 3T (3A) and his American clothes just don't fit unless there is the adjustable elastic inside.  Although I don't notice the same problem with his French clothes.  So I started wondering do French kids have smaller waists than American kids, really??  But when I see other kids at the playground, swim class, and at the grocery store, the answer is NO.  I have asked other parents about this problem and I think I might have discovered the secret.  Diapers.  Diapers really add to the 'backside' and kids need to have a little extra room to accommodate.  The parents of potty trained kids see this as a much much bigger problem than the parents of those kids still toddling in diapers.  For my little one, his clothes fit almost perfectly.

 So now I wonder do French parents potty train their kids earlier than American?  If you read this Link is says that the average kid is potty trained at 30 months, where the range is between 18 and 60.  While 30 months seems pretty normal, as my son was potty trained at 27 months, I wonder about the upper limits for that.  I know what in France, parents have a real incentive to have their kids potty trained at 36 months.  Without that, they are ineligible to  begin preschool, which is all-day and free for parents.  So if you want to save on child care then your kid will be potty trained by 3.  But in the US, does that mean that the average kid must wear pants with big waists to accommodate the kids not yet potty trained?

But wait, maybe I didn't consider one factor.  Maybe American kids clothes aren't really sized for the average American kid?  Americans in general seem to be taller than the French.  This is very anecdotal, but I rarely see a guy short than me in the US and in France it happened all the time.  My son wearing the same size in France and US, perhaps the average American kid his age are wearing 4T and therefore no longer have the extra backside?  Although the doctor does seem to think that he is 50th percentile for height and weight...  Oh well, in the meantime, I will have to find clothes with elastic in the waist.