I was trying to clean out the basement. That's my story, anyway. 

The thing that happened is the thing that always happens when I do this: I found a dusty old box filled with dusty old things. I opened it. Two hours later Sal found me sitting cross-legged surrounded by photos and newspaper clippings and delicate handkerchiefs that belonged to my late grandmother. 

One of the newspaper clippings was something that my mother had written when I left for college. As a newspaper columnist specializing in human interest stories, she occasionally had cause to write about things like this: the personal and poignant, those universal experiences to which readers could relate. This particular piece explored the emptying of her own nest: I was the youngest and the last to leave. She was worried about me being out in the world by myself. She was gutted by the prospect of not being able to ensure that I was safe. 

What struck me about the flimsy, yellowing, folded piece of newsprint wasn't the usual brand of nostalgia. Instead, I was reminded of something that had happened just five days earlier. I'd been visiting with my parents at my get-away apartment in Bend, Oregon and their car was in the shop. 

That was how my father, Kermit, came to ride a bike. For the first time in over 40 years. 

"Do you think it will hold me?" he asked. He's a formidable man. He's struggled with weight for his entire life. He had knee replacement surgery last year and before he could heal from that, his hips took a turn for the worse. He's hobbled up now and shuffles with an extremely pronounced limp, but hip replacement surgery is so expensive they've decided to wait two years until he qualifies for Medicare. 

The bike in question was a classic beach cruiser that I'd painted flat black and decorated with a No-Bozos sticker and Christmas lights. The bike, like my father, is a little quirky but built like a tank. 

"You're good, dad." I said, "Go for it."

My mother pedaled beside him on my other Bend commuter rig: a yellow vintage Bianchi Veloce folding bike with 20 inch wheels. 

He wobbled. He swerved. He struggled for balance. He came three inches from taking a digger straight into a flower bed. And then? He sailed. And smiled. And cackled his patented half-crazy laugh. And kept pedaling. 

Here I am standing in the middle of a neighborhood street watching my two aging parents ride away from me on bicycles that look like they are meant for children. Here I am, age 35, watching my father re-learn to balance. Here I am in the fall air, listening to them laugh and watching him veer and fighting the urge to run alongside him. 

My father – who struggles to walk. My father – who is so hopped up on medication for his extreme bi-polar disorder that he is sometimes a little confused and often stoned into a kind of crushing calm stupor (a calm, I should add, that we all prefer to the alternative bouts of depression and mania). My father – this big kid on a silly bike. Laughing.

They rode for a few miles before returning to the apartment so I had time to swallow back my tears and pull myself together. My mother rolled into the driveway and proclaimed the old folding Bianchi the "best bike she had every ridden in her entire life". Then she added, "I feel like I could ride up Mt. Everest on that bike!" My father was just behind her, still smiling.

Later that night we went out to dinner and my mother insisted on buying me the steak special for my belated birthday meal. I told them every single story I could remember from the Tour de France and my mother informed me that she "learned the twit thing" (Twitter) just so she would know if I was alive at the end of each day. "I almost pulled money out of our retirement to fly over there, Heidi." she said, "But then I figured we'd just freak you out: I knew you'd be ok."

I realized that, like the year that I left home for college, she still worries about me being out in the world alone. She's still gutted because she can't always be there to make sure I'm safe, because I choose to travel alone more often than not, because I'm always pedaling off into the desert or flying to India or trying to ride 2300 miles in three weeks. She raised an adventurer and now she has to pay the piper.

I also realized that it's a two-way road. I don't have children and I don't want to have any children, so I'll probably never really understand the way she feels, but every day I grow more and more concerned about how to take care of the people who took such good care of me. I worry about their health and their safety and their finances and their 20-year-old Jeep Wrangler. I worry about their stress and their diet and their crappy water well that never really provides enough water. I worry about their wood pile and how bad the winter will be and whether or not doctors are still occasionally accidentally giving my father near-lethal doses of experimental drugs.

I have an ongoing debate with them about how long I have to wait to start calling them elderly, a joke which makes me cringe internally as much as it makes us all laugh. My father's recent mobility challenges are a sobering reminder that despite what I may have believed when I was 10 years old, this towering strong man who once threw an entire six-drawer dresser over his back and hauled it up three flights of stairs is not, actually, invincible. As adult children we are forced to re-frame our relationship to our parents. And our aging, near-elderly parents, are forced to see their children in new light: no longer considered "dependents" we will become care-takers and helpers, as well as friends.

In my case, I will put a crazy beach cruiser under the man who taught me how to ride a bicycle, so he can find a place where his hips and knees function without pain and remember what the wind feels like and how good it is to get up a little too much speed and make threatening veering motions at innocent flowerbeds.