As much as my younger brother and I are friends now, the main memory I have of our interactions growing up is of us fighting. Often with words, sometimes with fists—occasionally, even in song. So when Juliette and I started talking about having a second child, I had a little apprehension about how Jason would deal with it.

But as it turns out, they really do seem to love each other so far. They have their squabbles, sure, but Jason is mostly caring and conscientious toward his sister. And as far as Eva goes, you can see from the picture that she adores her big brother.

That smile—the one she gives him when he plays with her—it wasn't something I was expecting, but it's one of the best things in my life.