"What was your most harrowing mothering experience?" I heard one mother ask another on the bench next to mine at the playground. There was a line of strollers in front of us. The kids, mostly toddlers, were on the slide or in the sandbox, sharing well or sharing poorly, while the adults had one eye on them and one on their phones. My eyes were neurotically fixed on the kids I had brought to the park, and there was a reason for it.The friend quipped:"Harrowing? Besides bursting out a little human from my body after spine-splitting labor for one full rotation of the earth?"They laughed. It wasn’t my question to answer, but I had known my response instantly:Disneyland. I had one six and one seven-year-old boy by the hand. It was a packed day, so the three of us, hand in hand, weaved through the crowd to get to our rides.Needing to pull out a map, I let go of their hands for maybe thirty seconds. Once I figured out where we were going, I reached for their tiny palms again. Only one reached back, so I did a 360º scan of my immediate surroundings expecting my other boy to be right there. He wasn’t. My breath tightened a little – I had seen too many movies with a child disappearing in the span of time it took to look at a watch – but okay, keep calm, this is real life. Real life with real pedophiles who stalk areas concentrated with kids!I squeezed my grip on the hand I did hold, pulling him this way and that, swinging my panicked head around clusters of vacationers. But my other boy wasn’t there. He wasn’t anywhere!My mouth went dry and my vision dimmed. The world – my life – turned black and I couldn’t breathe. Before my body completely shut down, I managed to spot a park security guard and pounced on him, yanking one boy out of two, by the arm.I must have looked ripe for the asylum with my tear-glazed eyes and dried-out mouth trying to make words. The white-haired guard was calm. He told me that in over fifty years, they hadn’t lost a single child. Whether or not that was true, it had the intended effect and I was able to take a breath and give him a description.My boy, it turned out, was already waiting at security headquarters. When I burst through the door, a woman security guard was comforting him as he cried. I wanted to float away with relief; instead, I knelt down in front of him so we were eye-level and told him that letting go of his hand was the worst thing I’d ever done. The guards suppressed smiles at my melodrama but I couldn’t be mad about it since they’d found my boy.I walked out with two out of two boys, taking their hands, convinced I’d never let go, not even when it was time to put them to bed. The amount of time it took for all of this to happen was, drumroll –under five minutes. Five minutes, and the darkest moments of my life."That was my most harrowing experience," I wanted to tell the two moms on the park bench, but they hadn’t asked me. Besides, I wasn’t a mother.I was the babysitter.I did crafts, made cupcakes, helped with homework, ran baths and read bedtime stories all those times they couldn’t.I was the temporary mom to all the kids whose actual mothers couldn’t be around, the one who had warm spit-up trail down her chest while burping their infant. The one who gently attached a hairpiece with forty-seven bobby pins to a teenage daughter’s real hair for an Irish dance competition the time her mother was called away on a business trip. The one who cradled a feverish son and placed cold compresses on his forehead. And yes, the one who clapped on every weekend in the family room as twin girls performed their rendition of High School Musical 1, 2 and 3 in their entirety."You see," I wanted to tell the moms on the playground bench, "I may not have burst out a little human from my body, but I know how to be a mother too."But did I? The day my world went black was when I lost a kid – someone else’s – at Disneyland. I couldn’t handle five minutes of high-tension worry. Yet there they were doing it, year after year, child after child. Mothers hush their worry of the world because they must. Maybe I wasn’t brave enough to do what they do. Instead I became a sometimes-mom, keeping my eyes fixed on their kids like an unblinking sentinel. After all, wasn’t that why so many mothers hired me, because I couldn’t bear the idea of unwatched children?