“I’m not baby. I Brynn!” This was your response to me the other day, and has been many times since when I say, “Here ya go, baby” and hand you your Minnie Mouse sippy cup. I can’t get over how your little toddler face has already perfected that Come on, Mom exasperated look.

Of course, you aren’t the only one who says stuff like this. I have also been hearing, “You know, you don’t have a baby anymore. Brynn is a full-on child.” And I look at you, my sweet little 2-year-old, and I see what they are saying. Physically, I see a tall, lean kid who runs and jumps and tries to sing the ABC’s and speaks in little sentences and wants her full head of curly hair styled like Poppy’s from Trolls.

My eyes see it. Yet, my heart doesn’t.

Last night you patted my tummy and said, “Baby in Mama’s belly” and gave your sibling a “baby kiss” (as opposed to a “big kiss”) and I wondered if that is where the “I’m not baby” came from. Do you think there can only be one baby for Mama at a time, little one?

I find myself wondering the same thing, my love. After having you, I was terrified of having another kid because I didn’t think I could love someone else as much as you. Now that I am pregnant, I love the baby growing in my belly, but it is still hard for me to comprehend how my heart is going to multiply once again so it can live in yet another tiny human.

Because that’s what happens, you know? My heart didn’t just expand to hold more love for you, my firstborn—it multiplied. And then when you arrived, you took my heart with you out into the world.

Every time you get sick, my heart hurts. Every time you cry “Mama!” in the night, my heart hears it and wants to go to you. Every time I see you being brave and daring, my heart skips a beat thinking about you falling. Every time you ask your dad if he is okay when he coughs, my heart swells. Because you carry my heart around with you everywhere you go. And your sibling will, too.

But it will be a different heart for them. They won’t take that heart from you, baby girl. The one you took from me the day you were born? You get to keep that forever.

When the new baby comes and our attention gets pulled from you—you’ll still be my baby.

When you start kindergarten not batting an eye going into your new classroom—you’ll still be my baby.

When you don’t want Dada and I to read you books, because you can read them yourself—you’ll still be my baby.

When you decide your friends are cooler than your parents and want to hang out with them instead of us—you’ll still be my baby.

When you get in trouble at school for talking too much—you’ll still be my baby.

When your attitude blossoms along with your body into teenagehood—you’ll still be my baby.

When you graduate high school and move away to college—you’ll still be my baby. If you get married and start a family of your own—you’ll still by my baby. And when I’m old and gray and you are not so young yourself—you will still be my baby.

That’s the thing I’m learning, little big one. No matter how old you get, or how many siblings you have, you will always be my sweet, sweet baby.