How to you document those flitting moments of childhood?

Over the course of my daughter's life I took thousands of photos to try to capture every moment...always feeling like I was grasping at air while relishing those moments in real-time. Now, as a grandfather, I enjoy watching her do the same - although she combines video and photos to document young Ellis' development. Below is her most recent video (January 2013). I hope you enjoy! And please share how you capture those special moments.