Will every birthday always be so bittersweet? My son turns three today and I found myself going to bed last night, pleading with the universe, not yet.

I’m not ready to move further into toddlerhood. I want one more day of being with my 2-year-old who I can convince myself sometimes is still more of a baby than a big kid.

Not yet.

Can I hold onto him a little longer as he currently is? Small hands that still look similar to his pudgy baby hands, before they grow into the long, thin fingers of a big kid who will dig for worms and take apart clocks to figure out how they work?

Not yet.

Can I bottle the sweet innocence of his mannerisms, how he can still react with wonder at my silly faces and goofy dances, and how we make up songs with nonsense words that don’t mean anything just because?

Not yet.

Can we continue to keep his entire world right in our household? Where everything he needs and everyone he wants can be found in one place, all under one roof?

Not yet.

Can we freeze time for just one more day? Keep the dump trucks and trains exactly where they are on the floor. Can I pause the clock when he’s in the bath, giggling at how I make the tugboat dunk in the water and pop right back up?

And yet.

I know it’s impossible to keep things as they are, and I don’t really want to. Because with each milestone we hit together, I grow, too. I transform and become right alongside my son, who gives me fresh eyes and reminds me what this life is for. To grow. And learn. And change. And experience.

And I don’t want to shortchange any of that. I don’t want any of the love and joy to stall or wait in a vain attempt to keep things as they are. Because as they are changes every day and as they are will become new things that will bring us joy and awe and wonder.

Each morning he wakes up—that I wake up—is something I never want to take for granted. The ability to keep growing and loving every day is never a given, so I don’t want to forget how precious tomorrow really is.

So I will continue to cheer at each milestone we hit—when he learns to tie his shoes, when he masters how to make breakfast, when he starts to sleep in instead of waking up, begging us to play.

I will celebrate the steps he takes away from us. The friends he will make. The activities and the people who will join his world.

I will swell with pride at the human that he will be, making his place in the world.

Are we ready to face three, and all that it means?

Not yet.

But we will, together.

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