It is one thing if you say something like "Our afternoon was great." or "Our matching Facebook profile picture is creepy and we need to fix that." or even bordering on "Can you pick up our dinner for tonight."
But when that inner planner, that part of yourself you hide from almost everyone, except your close and admittedly screwed up friends, comes out... that moment is defined as "when it got serious."
That moment defines if he, or you, will freak out. When you are accidentally on a ring site picking out which $12,400 Tiffany's engagement ring is perfect and then he goes to check a game score and sees. That moment when your friend says "Oh you should do that for your wed... uh for my wedding!" when she is married already and he is clearly one step ahead of the left of half of that word and realizes you two have already been planning the big event. Or... the mother of them all... when you talk about being a mother. With him.
Now it is a given that every girl (save for the ones who hate children and men) plans her wedding from the first time she sees a Disney movie and starts playing with baby dolls from birth. But I feel like since hitting age 20, I see babies everywhere. And not only do I see them, but I have a sickening, horrifying need to steal/abduct/kiss/have all of them. Sure, it is nice to look at them. But I want to put their squishy fat legs in precious CSU and Notre Dame onesies. I want to put them in stockings and pretend they are presents. I want to dress them in baby cow outfits for day to day activities. I fantasize about babies. And not just a baby but lots of them. A sweat shop work force amount of them. Not a bad idea either, if you are talking about getting a return on your bodily investment in having one. Kidding, kidding. Look what that did for Nike.
It is that moment, when one of you (because this is not only just the girl who will bring this up and I know that for a fact) brings up your children as in "our" children, that is when you know it is serious. Sure, "I love you" takes it up a notch. But saying "I would like to create another life and therefore be stuck with you involved in mine forever" is a different level of crazy.
When that "My kids will be swimming quarterbacks who ride horses and love calculus and want to play for ND and the Broncos and cook their mama dinner on Sunday after Mass" type of thoughts occur, and when they accidentally slip out in regular conversation because your 20 something brain is in baby mode because your body is saying "WOMAN you crazy, I am prime-o for baby making and you are wasting your time doing statistics you fool!" you realize that you are no longer in a high school relationship and it is time to buck up and embrace the fear of "ours."