This is kind of belated, but last week my daughter Isabel turned two years old, and in the days since, I've started to realize just how quickly our kids have grown up. I experienced this with my son, of course, but this time there's something different. Since the wife and I are set on only having two kids, I know that I'll never see this again, and a little part of me is sad to see that go.

And yet, it seems like just overnight my daughter has grown in leaps and bounds. She speaks so well, and understands so much, and frankly, she's bigger than I expected. That's partly because my son has turned out to be something of a small fry, but also because she's above average height and weight for her age group.

It's kind of shocking (and amusing) to see my two kids next to each other and think that they look almost the same age, even though they're two years apart. That's part of the fun of siblings, I suppose, to have a companion and playmate that is just as willing and able to share as they are to duke it out. With these two, at least it'll be somewhat of a fair fight.