The first time I run into Marilyn it's because I'm racing down the street to claim a shoe that Samantha threw out of her stroller. We exchange a weary, we've-all-been-there glance and I head on my way. A week later we see each other at the park. This time, we chat. It turns out she and her husband have an apartment around the corner from us. We exchange numbers and I walk home with an extra spring in my step.