“Thonk!” The first time I heard the sound in my new home I didn’t jump or react, even though I knew that on the other side of the glass was death. “Thonk!” goes the bird as it collides squarely with a window, and then is no more. The sound is unmistakable: like the crack of a baseball against a bat in the near distance outside on a hot summer evening. But unlike the happy nostalgia of a ballgame, this sound carries with it the weight of a body. The first one was about four months ago now. My 17-month-old daughter Zelda was in her high chair. She had been stunned by the sound and made her “surprised” face, looking around for the source of it. I wanted to go out to the bird, but I didn’t want Zelda to know that anything was wrong: My instinct was to hide this event from her. I peeked outside the window and saw a very small House Sparrow by the window, heaving heavy sighs on the ground. Life had to continue: We needed to go to the grocery store. When we...