At fourteen months, Evan made the transition from crawling to running. Suddenly, he slept much better at night, maybe because he raced around like a rocket all day. I went from endlessly soothing a baby to frantically chasing a toddler. Evan didn’t seem to have a sense of his own space. He ran into walls, fell off chairs, and walked in front of moving swings. At the playground, he was a threat to himself and others.

He didn’t fear strangers. He didn’t believe other kids ever wanted to play alone. He ran into groups, elbowed his way into other children’s sandboxes. He had this hundred-watt smile and these brilliant blue eyes. At fourteen months, it was as if the world already wasn’t big enough for him. He had so much to do, so much to see, and so much to say.

An older woman once sat beside me on a park bench just to listen to the magic of Evan’s laughter as he rolled in a pile of fall leaves.

“He is an old soul,” she told me before leaving. “A very old soul. Watch him. Listen to him. He will teach you what you need to know.”

Around this time Evan stopped wearing clothes. He’d always cried if we dressed him in anything other than cotton. Now he refused even that. I found shirts, socks, pants, diapers strewn down the hallway, and sometimes across swing sets. I put the clothes back on. He took them back off.

We stayed home more often; naked eighteen-month-olds weren’t always welcome at a public park.

Evan also started some new and alarming habits. For example, he took to climbing onto the kitchen counter so he could play with the knives. He liked to hold them by the blade, as if he needed to slice open his palms in order to understand how sharp the edges were. The same went with the stove. I gave up cooking unless Michael was home. Evan was obsessed with the burners. The more we told him they were hot, the more he needed to place his fingers across the glowing red coils.

It was like living with a bull in a china shop. One day he broke all the eggs in the kitchen in order to hear how they would sound (I was on the phone). The next afternoon, he smashed every bottle of perfume I owned against the tile floor, to see how far the glass would shatter (I was in the downstairs lavette). I caught him climbing the china cabinet one afternoon, and wisely padlocked the doors (I’d been in the shower, but realized I couldn’t hear Evan and went bolting through the house in nothing but a towel).

We saw our first expert, a child development specialist. We received our first diagnosis. Evan suffered from global Sensory Integration Disorder; his brain was properly receiving input from his five senses, but could not prioritize the sensations. Meaning he existed in an overstimulated state-a full cup, the specialist explained to us, where each new sound, scent, touch, smell, and taste was another drip, drip, drip into an overflowing vessel. Some things he could not tolerate at all: the rasp of a zipper, the feel of denim. Other sensations he fixated on, trying to get them to penetrate the clutter of his brain-what is sharp, what is hot, what is pain. He was like a moth, drawn to the flame.

Evan started to receive occupational therapy. Michael agreed that I needed help, so we hired our first in a string of what would become fourteen part-time nannies.

I went on walks to clear my head and refresh my body. Then I came home to my crazy, exuberant wild child. He would bowl me over with his hugs. Light up the world with the exuberance of his laughter. We would wrestle, tickle, and play endless games of hide-and-seek.

Then he would scream over having to brush his teeth. Or fly into a rage over having been served pasta on the wrong-colored plate. He threw one of Michael’s golf balls through our family room window when we asked him to put on shoes. He slapped me across the face when I told him it was time for bed.

Our first nanny quit, then the second, the third.

When Evan was happy, he was so happy. But when he was angry, he was so angry, and when he was sad… he was so, so sad.

We received our second diagnosis: Mood Disorder NOS (Not Otherwise Specified). At four, we put him on clonidine, a drug generally used with ADHD to help moderate impulsive and oppositional behavior. We hoped the clonidine would take off the edge, allowing Evan to find some measure of self-control.

He improved in the short term. Slept better at night. Less manic during the day. Between the clonidine and a one-to-one aide, it appeared he might survive preschool.

Time, Michael and I told ourselves. Evan just needed time. Time for the occupational therapy to assist with the hypersensitivity. Time to better develop his own coping skills. We had challenges, but all parents had challenges. Right?

Evan started kindergarten. He interrupted the teacher. He laughed at inappropriate times. He screamed if told to stop doing an activity he wanted to do, and refused to engage in an activity he didn’t want to do.

In the first eight weeks, Michael and I were summoned to the school nearly a dozen times. We sat there self-consciously. Well-groomed, professional parents who had no idea why our child was a five-year-old hoodlum. We loved Evan. We set boundaries for him. We fought for him.

Still, Evan wanted to do what Evan wanted to do and he was willing to employ any means necessary to get his way.

Third and fourth diagnoses: ADHD and Anxiety Disorder NOS. At the school’s insistence, we put him on the antidepressant Lexapro. Lexapro affects the serotonin levels in the brain. We were told it would calm Evan, help him focus.

Your son’s brain is a busy, busy place, the specialist told us. Imagine standing in the middle of a parade and trying to remain still while hearing the horns blow in your ear and feeling the marchers sweep by. Evan loves you. Evan wants to do well. But Evan can’t exit from the parade long enough to be Evan.

We dutifully filled the prescription. It’s the American way, right? Your child is disruptive, misbehaving, nonconforming. Drug him.

Two weeks later, while quietly sketching a picture of a race car, Evan sat up and drove his pencil through the eardrum of the five-year-old girl sitting beside him.

That was the end of kindergarten for Evan.

Later, we learned Evan suffered from a paradoxical reaction to the Lexapro. A paradoxical reaction is when a drug has the opposite effect than intended. For example, a pain reliever causes pain. Or a sedative causes hyperactivity. Lexapro was supposed to calm our son. Instead, it sent him into a new orbit of agitation, and he acted accordingly.

We found a new doctor for Evan. Best Ph.D. in Boston, we were told. I hired nanny number nine and settled in to home-school Evan.

Michael started working longer hours. Gotta pay for the specialists, he would say, as if I couldn’t smell the perfume that lingered on his coat, or see how many times he checked his cell phone for text messages.

I wondered if she was young and beautiful, maybe with frosted blonde hair that didn’t suffer from neglected roots. Maybe her womb had never filled with poison. Maybe she could take her son to the grocery store without him hurling produce at the other shoppers. Maybe she went to restaurants without her child dumping pasta on the floor and making handprints out of red sauce.

Maybe she slept through the night and read the newspaper each morning and could converse wittily on a variety of adult topics.

Or maybe she just giggled, and told Michael he was perfect.

You try as a parent. You love beyond reason. You fight beyond endurance. You hope beyond despair.

You never think, until the very last moment, that it still might not be enough.

It’s four in the afternoon on Friday, and the sky is dark with thunderclouds. Given the intense August heat, most people are grateful for the upcoming relief. I don’t care. I left the house five minutes late and now I’m driving too fast, trying to make up for lost time.