I used to spend my days with a tiny little girl. She had curly hair, barely contained beneath her giant headband, that bounced when she walked. Her eyes would squint up when she laughed and her smile would elicit sounds of “aww” from people all around.

That smile was a thing of beauty and I still find myself staring in the general direction of where it once came from. I search the passenger seat of my car or the chair across the breakfast table. It’s still there, I think to myself. Right? Was it all a dream?

What?

What what? Nothing.

Why are you staring at me?

Because I remember when you were a baby. I’m allowed. It’s a free country.

Ugh.

At this point, the moody teenager in my house stands up. Her hair still bounces when she does and her adorable face is now more beautiful in the conventional sense. There are no more Cabbage Patch cheeks or rounded chin. She’s a little lady. Her smile still lights up a room…but it doesn’t show up as easily as it once did. Now she’s leaving the room.

Come back later. We can watch TV.

Maybe. I have homework. Now I’m spending time standing here. Can I go?

Can she go? What a question. This is the same little mook who used to chase me around all day asking what we could play next. Exhausted evenings were spent watching Liv and Maddie and making art together. We’d play the “drawing game” or, worse, “attack.” She’d run up and punch me, causing a melee of playfighting all over the house. I couldn’t keep this kid off of me.

Well excuuuuuse me. I’m sorry if I’m keeping you. You can go.

It’s OK. Thanks. Maybe I’ll come down later.

“It’s OK. Thanks”. This kid doesn’t understand sarcasm. And she’s gone.

The weirdest thing is that this transformation from Romper Room to Romper Rude happened overnight.

Actually, let me explain that part a bit more because it’s a real study of time dilation. For me personally, time feels as though it has moved slowly. The person I was when my kids were tiny is vastly different than who I am now. For others my age, life may have stood still. For me, it’s been a train ride at breakneck speed.

Since the arrival of my kids, I have had major heart surgery, stopped speaking to most of my family, gotten divorced, completely changed my writing career, and moved into a new home. My diet has changed, my stress levels have changed, and my conditioning has changed. The only thing, for me, that has remained constant is my name.

So when I look back to 2010 in my own timeline, it feels like a million years.

When it comes to the kids, though, 2010 was last week.

People would warn me back then that “it goes by quickly”, but that felt like nonsense. How could it go by quickly? At the time, the days lasted for years. There were diapers to change and things to buy. Life was long and nothing went by “quickly”. As I just pointed out, my own life has been through an incredible transformation. Nothing about any of that happened “overnight.”

Why did my daughter seemingly grow up overnight then? Well, it was the slow burn that did it. My little princess didn’t mutate into this scowling high schooler in a sudden moment. Rather it was a gradual build from human American Girl doll to supporting cast member of 90210.

Sadly, I can even pinpoint the day that I first noticed it happening. She would come home from elementary school and go right to her homework. As soon as she finished, I would hear her little feet pattering against the floor and growing louder until she would burst into my office. From there, it was a barrage of TV and games. I loved it, but it would also come at inconvenient times. Work would go on hold and obligations had to wait until I eventually tucked her in.

Then, one day, it happened. I heard the zip of her backpack followed by that familiar patter. I prepared for her to come darting in. Only this time, the pattering grew more distant until I heard her upstairs door slam. She went into her room to do whatever it is kids do in their room. I sat there dumbfounded with a lot more time on my hands than I ever had before.

That doesn’t mean we never hung out again or that she changed overnight. There were many days after that when she came running to me. She may have even come back later that night. That’s what made it all feel so gradual. That’s what forced me to not even notice the baby girl slowly being devoured by the lady who lives with me now.

This woman watches television with me still. We talk about our lives and have a stronger relationship than we ever had before. I even “tuck her in” at night, which is nothing more than running up to her room and saying goodnight. I can confidently say she’s still my baby girl, even as she’s grown up. One day, she’ll be 50 and still my baby girl.

Do I miss that baby? More than you know. Would I trade this girl in my house to get her back? Well, sometimes. But mostly no. (hey, you wanted honesty) I am proud of who she has become and how all that time together has created a bond that we will hold onto forever. I’m the luckiest dad in the world because I got to experience the joy of being her father then and now. It’s not about how old she is. It’s about who she is and she couldn’t be better.

Listen to people who tell you to hold on to those moments. Let them tell you how they go by quickly. Then, use those moments to build the relationships you want to have when they’re grown. Because one day, that baby will be gone and the relationship you have with the adult who takes their place will be built upon the work you do when they’re young.

If you do that, you’ll never miss that baby. She’ll always be there. Mine is.