This week, as the summer days began to get the tiniest bit shorter, and the nights had the slightest hint of crispness, I realized that I’d better make good on my promise to teach my daughter, nearly 6, to ride a bike. Getting rid of the training wheels was one of a few summer promises Kira and I had made to each other at the end of June. And we hadn’t touched the bike since.

One morning, I gulped down my last bit of coffee and told Kira I was ready. “Put on your sneakers and helmet, and let’s get on the bike,” I said enthusiastically.

Sporting my new Asics sneakers, I was definitely counting on this exercise as my weekly trip to the gym. After convincing Kira that I wouldn’t let her fall, I started racing behind her, holding the back of her seat as she pedaled away. There are some children who get their balance instantly, and after a few minutes are riding by themselves. Suffice it to say, Kira was not one of them.

Not that she was hopeless. After a little more than an hour, I was occasionally letting go for a second or two or three and she was pedaling on her own. I was also drenched with sweat and ready to collapse.

“Okay, Kira,” I said between huffs. “Let’s take a break. We’ll do more riding tomorrow.”

She protested, saying that she wanted to keep riding for eight hours. I didn’t even have the energy to respond.

But believe it or not, the next morning, there I was, running alongside Kira.

“Pedal faster when you feel yourself wobbling,” I yelled. “Stop looking down,” I hollered. “Steer, steer, steer,” I bellowed. These, of course, were said in between many proclamations of “That’s it,” and “You’re doing it,” and “Unbelievable.”

As she finally took off, with a newfound confidence in her ability to keep balanced — as well as a newfound ability to put her feet down when she lost this balance — I had only one thought.

It wasn’t something sentimental about being proud of her, or something syrupy about the passage of time. The one, pulsating thought was: “My back, ow, my back.”

As I hobbled back into the house, contemplating just how many Advil I could possibly take, it occurred to me that I had two more children to teach to ride a bike. It seemed unlikely that my normally very involved husband was going to pick up this particular piece of slack. When he saw Kira riding, he told me that he was sad that he hadn’t taught her to ride the bike. But I don’t think he was sad enough to throw out his own back.

It is David, 13 years older than me, who has recently found a way to silence my little digs about his nearing the big 5-0. When our fifth child was born in January, I teasingly asked him if he knew how old he’d be by the time we took Nate to college. Instead of doing the math, David deadpanned, “Who cares? I’ll be dead by then.”

I realized, though, that in five years, my eldest son, Jacob, now nearly 10, will be at the perfect age to teach his younger brother to ride a bike. And he even seemed excited about this prospect.

It is this age gap between my first and fifth that often troubles me. My oldest is ready to go on an adventurous hiking trip. My baby isn’t. I want to take my oldest for a long bike ride. But I need to be back to nurse the baby. My oldest has questions about his homework just as I’m putting the baby to bed.

Having a lot of children is exhausting, but nearly always feels manageable. Trying to meet the needs of both a fifth-grader and a baby, though, occasionally feels impossible.

When I get frustrated by this quandary, I try to remind myself that not always meeting my children exactly where they are, and exactly when they need me, might serve them well later on in life. And so might the experience of teaching a younger sibling how to ride a bike.

And even if it doesn’t, too bad. There are only so many Advil tablets one can take in 24 hours. Or in a lifetime, for that matter.

sarasberman@aol.com