Despite his nickname, Little Bird has always strived to be big. When he was inside me, he wouldn’t just kick, he’d stretch, his feet jamming into my organs. He arrived 3 1/2 weeks early, scrambling out into the world unexpectedly. Now he’s been with us for more than six months, a half-year full of so many changes.

When Little Bird arrived, he was a peanut, just over five pounds. As Sprout said, “He’s so teeny tiny!” Because he hadn’t gained most of the fat babies do in their last weeks in utero, his wrinkly face looked especially old-mannish.

These days, he’s still skinny – 0% weight but 70% height – but has filled out a bit. He no longer swims in pajamas that match his age. His face is heart-shaped, with blue eyes shining under a big forehead. His hair, which started as just strings stuck to his forehead, has grown out to a little tuft of spikes and then to the start of a real head of hair.

He’s sturdy enough that I can show him far more affection than when he was born. I give him real hugs with a bit of a squeeze, no longer afraid I’ll break him. When he’s on my shoulder, I nuzzle my nose into his side.

As he’s grown physically, his personality has too. He’s always held his eyes open wide, with a default surprised expression. Now when he’s excited, his mouth and eyes burst open into an all-encompassing smile. Bopping him on the nose often inspires this expression. Walking through the door, he looks at me, grins, and then hides his face in Chris’s shoulder. To show excitement, he thrashes his feet, kicking so hard that he loses his socks. When he’s content, he presses the soles of his feet together. As he nurses, he clasps his hands together or pulls at my shirt.

Little Bird has started paying rapt attention to his senses, from whomever is talking to ceiling fans. He’s started trying new sounds just to see if he can. It was raspberries, then baby bird squawks, then screeches. (Which of course, Sprout joins in for.) When I’m burping Little Bird over my shoulder, he rakes the back of the couch with his fingernails. He grabs things with quick hands, including my hair and cereal bowl. If he could, he’d grab the spoon Chris uses to feed him solid foods. Instead, he leans forward and chomps before it reaches his mouth. Butternut squash, sweet potatoes, avocados, and applesauce have all been met with enthusiasm. He’s finished dinner with a totally clean bib.

But it’s not all fun. He can give you a serious “What the hell?” look, although he can’t raise his eyebrow. He’ll express his distaste for a situation with a whimper that ascends to a wail. The most common culprit is the lack of a nap, exacerbated by the fact that most of the time, he’ll only sleep in the car or the stroller. The car nap often only occurs after a crying jag of 10 minutes or more. (As Ilana Wiles interprets her daughter screaming in The Mommy Shorts Guide to Remarkably Average Parenting, “I CAN’T HANDLE BEING IN A CAR AND NOT MOVING AT THE SAME TIME!”) Between his and Sprout’s hatred of sleep, it results in some rough going some days.

Not only is Little Bird himself very different than Sprout, but so is my perception of time. Sprout’s infancy seemed to pass slowly. Each development was huge and well-documented. The months stretched out to accommodate the newness.

Now, our time and energy is split. I’m less likely to pay close attention to Little Bird, just because he’s not the only one. It seems he’s grown so much overnight, making me feel like I’ve missed out on something. Was I not paying attention enough? When did he get so big, so attentive, so much of a little person? Julianna Miner, who writes Rants from Mommyland, describes the years parenting small children as The Blur. It feels sometimes as if I’m watching a movie on fast forward.

I’ve made an effort lately to slow down. I watch Little Bird’s sweet face while he’s nursing, only turning to my phone when I’m on the edge of falling asleep myself. (That’s approximately 30 seconds, but at least it’s something.) I’ve been playing with him more, shaking rattles and tickling his little sides. It’s never enough time, but I do the best that I can.

In six months, so much growing has happened, for all of us.