At exactly 1:34 p.m., my heart stops. It’s a Friday. The voice on the phone has just spoken words no mother wants to hear: “Mrs. Green, your son is missing.”

Instead of racing — which would be cliche — my heart seems to stop.

“He wandered from the playground at recess. We have staff out looking for him. I’ve called the police.”

“I’m on my way,” I hang up and sweep the counter for the car keys. I could say that my stomach falls out (another cliche), but really, I have zero awareness of my body. Nor do I have any recollection of peeling out of the driveway and driving to the school, about three miles away.

The absence of feeling in those minutes is what stands out. Hands clenching the wheel, the signaling, steering, the braking and changing lanes — it all happens with me, without me. All I can picture is a boy clutching a big blue ball to his chest as he crosses a busy overpass. The blue ball he insisted on bringing to school with him this morning because it’s Fun Friday.

My 10-year-old — a gangly preteen in Adidas tracksuit pants — has autism. He may not remember to look both ways before crossing the road. He will probably talk to strangers, even though we’ve had that “talk” a thousand times. He will tell them a bunch of things he shouldn’t and forget to tell them the things he should. He will believe anything you tell him. He is oh-so-vulnerable, my boy. He looks just like any other kid his age. He is nothing like any other kid his age. His difference is not a blessing, but it’s not exactly a curse, either. It’s complicated.

Letting go is tough, especially when your kid has autism. You grow accustomed to your child needing extra support. You come to depend on your kid depending on you. It can be hard to know when to let go and how to let go. Of course I want my son to live his own life. I want him to be independent — as independent as he can be. I want him to grow into a capable young man who can take pride in his accomplishments, even if I don’t yet know what those accomplishments will look like for him. It could be going to college; it could simply be going to the corner store to buy milk. No parent knows what the future holds or how their kids will turn out. What I do know is that letting go is the hardest, most necessary thing I have to do.

When my son, Jackson, was diagnosed with autism, and later ADHD and anxiety, all the developmental milestones went out the window. He charted his own course. A tortoise in some respects, a hare in others. Over the seven years since his diagnosis, I’ve come to learn that it doesn’t matter how or when he gets there. I must trust that he will get there eventually. But without the usual markers on the road, we are driving blind. How can I know when he’s ready to learn a new skill or take on a responsibility? Most children follow the curve and develop alongside their peers. They naturally progress and move through several rites of passage, from sleepovers to walking to school alone.

Jackson does not walk alongside his peers. He has never once asked to have a sleepover. He is quite content in his orbit, thank you very much. He has a couple chores. Many broken dishes later, he can now set the table and empty the dishwasher. After numerous spills, he can pour his own glass of milk. I have fought the urge to swoop in from the sidelines, to help or simply take over, more times than I can count. “Back off,” I have chided myself. “You don’t know what he is capable of unless you let him try.” Neither does Jackson.

Not long ago, we traveled by train to visit his grandparents. At some point he needed the bathroom.

“I can go by myself, Mommy,” he reminded me. “I’m a big boy.”

Ten is a tricky age — too old to be accompanied, yet too vulnerable to go it alone. Public bathrooms are a source of incredible anxiety for parents like me.

"Go and come right back,” I said, biting my lip.

As soon as he left my side, I felt sick. I stared at the lit “occupied” sign at the end of the train carriage, a million thoughts hurtling through my head. What if he needs my help? Will he remember to wipe properly and wash his hands? What if he can’t unlock the door?

He's fine, a voice breathed in my ear. He's taking too long, another voice interrupted. Something must be wrong. You should check on him now.

I fidgeted in my seat, willing the “occupied” light to go off. Willing my happy boy to saunter down the aisle back to his seat. Back to me.

Still, Jackson didn't come.

You learn from doing. I know this. As a sheltered only child, I know better than most. At 22, I headed to the United Kingdom with nothing but my naivete and a backpack. Thousands of miles from home, I was living in hostels and looking for work. It was terrifying and exhilarating. With each passing month and every setback, I grew up. I had no choice.

Now, I am repeating parenting patterns with my own only child — putting the “mother” in “smother.” Letting go goes against every instinct I have to protect my innocent boy from a world that doesn’t understand (or fully accept) his way of being. What if Jackson gets hurt? I would never forgive myself.

Just then the light went out and the door flew open. My boy marched down the aisle, a huge smile on his face.

When I race into the school office and see him sitting there, my heart kick-starts.

“Mommy,” he says. There is that huge smile again, lighting up his face. He sits across from the principal, still clutching the blue ball to his chest. “I was walking home. Aren’t you proud of me?”

At that moment, because I can’t speak, I crouch and pull him into my arms. He doesn’t protest. When I bury my face in his soft brown curls and hold his face in my hands, I notice how doughy-soft his skin is. He still has baby cheeks. For now.

Formerly a featured blogger at Huff Post, Julie M. Green is a freelance writer whose work has appeared in the Globe and Mail, Today’s Parent, She Knows, CBC Parents and more. She lives in Toronto with her husband, son and bulldog.

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