Last weekend my daughter turned two years old. I remember everything about the night she was born: how all day I had known the contractions were real, timing them after dinner and calling the midwife, being expected to give a family medical history to the nurse at the hospital when there’s a bowling ball raging against my hips, having my dose of Fentanyl wear off and begging for a second, just to be told that no, it was too late, pushing her out using every inch of my being, and then savoring every second of the Golden Hour. Yup, it’s all right there at the top of my memory, like sea foam.

Her hair is turning a dark blonde with some red. She’s tall for her age, and slender, although she can really put away the food. When she smiles, which she does often, I can see she is losing her underbite, which the dentist said she would. I think her underbite is adorable, but I guess looking less like a bulldog is a good thing. Her walking and speech have been delayed, but in the past couple weeks she is closing the gap rapidly. Lately when I nurse her before bed she gives me a sassy smile as she sucks, and her eyes wrinkle into crescent moons, and if she’s lying on her left side I can see her dimple.

After two you can no longer say your baby’s age in months. Because after two, no one cares about the months. After all, no one goes around saying, “my son is 31 months” or “my daughter is 42 months.” Just like you don’t give your height in inches, except maybe at the doctor’s office. The best you can hope for later this year is being able to say that she’s two and a half. Unless there’s a specific concern about development, measurements for milestones tend to generalize to six-month periods or longer. Clothing sizes fizzle out to 2T and 3T and beyond. No more of the 18-month stuff. These are cold, unsentimental reminders that time is racing on, leaving behind soft baby coos, first “Mama”s, and first baths together in the big tub. No longer is she content to sleep on your chest where she snuggles up to your heartbeat – she wants to play tip-overs on the bed. No longer are you the most reassuring thing to her – her stuffed Boo is. It’s heartbreaking, but amazing too – your last baby is growing up.

So you settle for the half-year demarcation, out loud anyway. Inside she will always be the months.

You don’t harbor any illusions about what you’re in for; you also have a 4-year old. He’s tenacious, sensitive, intelligent, terribly willful. You went through the Terrible 3s and the More Terrible 4s with him. So far Sister is headed in the same direction. In fact, the other day you glimpsed the Terrible 2s. Already. Oy.

But still, you distrust the days because they are deceptive, and time is a thief. Days claim they are slow and churning: the disarray of breakfast, hovering to make sure she and her brother eat instead of feed the dog, the demands of finding lost shoes and stocking the diaper bag and wow baby, you pooped again? and Big Brother, don’t push your sister, the constant and grinding discipline and the nonexistent naps and the laundry piles and “No! Me!” and she has to start all over because you made a move to assist her with her sandal. But folded within the blur are the “I love you”s, the sibling hugs, the unassisted steps, and silly dance parties. You curse the moments that repeat themselves over and over, and you chase the moments that don’t ever come back. Time lies to you that way, and coaxes you into thinking it will go on forever, particularly in moments of boiling, seething anger and exhaustion. Then pretty soon you are running after it, screaming that you want back the first smile, the belly button discovery, the newborn smell. You want it all back.

Just for a little while.

Why does the good stuff go so fast?

Always be the months.