How did you get that big?

Human biology really is incredible. Two years ago I was hosting a cluster of fast multiplying cells. Today I have an energetic genuine human being crawling around and giggling. How does it happen? (Now settle down; I know how it happens, I do not need reminding) But how does one moments, one event, one relatively very small period of time, one meeting of people who may be very close or may barely know each other, how does that suddenly become another entirely different human being? How is it allowed without fireworks, a fanfare, something magical to mark that a new creation is taking place? I often wonder about it when I watch my daughter. I could just watch her all day, discovering new things. She has just worked out basic shape sorting and stacking toys and her new favourite game is "putting things on grown ups heads". It looks like she is trying to sock you in the eye with Rabbit; she is actually trying to give you a new hat. But how did that come out of something that seemed so insignificant at the time? When her father comes to visit, I often wonder if he thinks it to but isn't brave enough to say either. How did we, now so separate, make a truly wonderful person not just with ten fingers and ten toes but with a cheeky personality, a mind and a set of thoughts all of her own?