Babies are fascinating. They’re such creatures of pure, unfiltered instinct. There is nothing remotely deceptive about them. They aren’t even particularly innocent, not in the same sense that an older child is. My four-year-old believes in fairies and unicorns and magic. My four-month-old will give the same baleful stare to the garden centre Santa as she gives to most objects, furry creatures and toys crossing her line of vision, no matter how eagerly they are shoved into her face proffered. The four-year-old will give us increasingly rambling, far-fetched explanations as to why she needs two puddings despite not having finished her main dinner. The four-month-old will desperately mouth anything that comes into contact with her face. It’s a crude analogy and I apologise for it, but sometimes she really does remind me of the walkers from The Walking Dead. She responds to the purest, basest instinct to feed. We even call babies’ mealtimes “giving them a feed,” like we’re dehumanising what they’re doing because it’s so unlike what it becomes – three solid meals defined by the time of day. Babies don’t eat when they’re not hungry. They don’t graze or snack. They take in exactly what their body needs when they need it. They feed. Like animals. Like zombies.

When my eldest was a baby I remember being puzzled by this sense that she didn’t seem to have this innate innocence that little children are supposed to have. I now realise that it’s because this comes later, with the rudimentary understanding of the world that toddlers develop. Babies are only innocent in the very simplest sense of the word. Nothing much has happened to them yet. They don’t know how to be naughty or manipulative or deceitful. They also don’t know how to take you at your word when you tell them that magic is real. You look at their eyes and you find yourself wondering: what do you really know? What will you lose, as you grow? When will she realise that my bare arm isn’t food, though it’s warm and made of flesh? When will she realise that people still exist even though she can’t see them? When will she bring a toy to her mouth and not suckle?

You forget how fast they grow. The four-year-old comes out with new phrases perhaps once or twice a week and you think, “Wow, where did that level of comprehension come from? How did you piece together that logic without anyone showing you the map?” But the four-month-old changes almost daily. She studies your face and waits for you to smile before she does. Everything is a new challenge to study, from a fallen leaf to the route out of the dreaded car seat, not to mention those puzzling-but-awfully-tasty starfish things at the ends of her arms. She arches and levers her body until it moves, rolling the world into something new all over again. She hears your praise and files it away. This is a good thing. I will do this again. You put her into her cot and make it dark and she remembers that this means sleep. She wakes up alone and cries. You appear and she grins because it’s you, and you exist.

The love is the purest it will ever be. She loves absolutely and unconditionally because you keep her alive; but she also needs you absolutely and unconditionally to keep her alive. When your body is broken and your head is pounding she needs you. When you haven’t slept and your brain feels like something has crawled into your ear, curled up somewhere around your thinking parts and died, she needs you. She doesn’t care about the funny or the clever things you say. She doesn’t think you’re pretty. She doesn’t think you need a break. She doesn’t care about your great personality or that you lost 2lbs this week. She just needs you.

No one will ever need you so much as your babies. No one will ever love you quite the same way. And no one will ever be quite so fascinating.