Our relationship has always been somewhat strained.

There is an edge, a certain wariness. Something that neither of us talk about.

Sometimes, we just struggle through it. But more often than not we just let it hang in the air, a cloud of mistrust, fear and the evolving realization that we are more alike than either of us can imagine.

Today, he seems different. More confident, relaxed.

Me? Not so much, save for a recent dose of clarity.

Today is his 15th birthday, but it was earlier this week that Matthew became a man; that he became what I always knew he could be.

And  I could not be more proud of him.

It was a warm day, a holiday. There was another lawn that needed to be mowed.

The Rent-A-Teenager program we started just a few days before was flourishing. The phone was ringing off the hook, and both Tim and Matt were adjusting to the sudden influx of responsibility and the world of work.

Tim, my oldest son, was grumpy and tired. He was dragging and stalling.

I did what I do best: I got frustrated. “We committed to this job,” I barked. “When we say we’re going to do something, we do it!”

Tim shrugged. It was a job he committed to, but he was not feeling well and wanted some more time to wake up before leaving.

I had my own struggles. I had planned a window of time to help the kids with their business, but I had lots of other plans and the clock was ticking. There was a barbecue with friends, bills to be paid, laundry . . .

Another 10 minutes went by, and I loaded the mower in the truck. Tim was sullen, angry. “If you won’t do it, I will,” I huffed.

Matthew watched the exchange between me and his brother without commentary. He had the day off. He had his own holiday plans.

As I was backing the truck out of the driveway, he flagged me down. “I’ll do it, Dad,” he said.

We rode to the job site in our typical silence. I was concerned. It was a good-sized lawn, and I assumed most of it would fall on my shoulders.

I was judging Matthew the boy. I did not realize then that I was riding with Matthew the man.

We got to the site, and I gave him the instructions. He listened carefully before helping unload the mower, the trimmer and a push-broom.

To stay on schedule, I started the trimming, but kept a careful eye on Matthew with the lawn mower. I have high expectations. I am demanding.

But Matthew never wavered. He was sweating in the direct sun, but kept the lines straight. His eyes were fixed on the ground before him, carefully watching for rocks. He never stopped. He never paused. He never complained.

When he finished the mowing, he carefully inspected his work before sweeping the walkway without me telling him to do it.

He wanted that lawn to look good, perfect.

We returned home in silence. Two men who just finished a job. A father and a son.

The silence was comfortable, familiar for both of us.

I snuck a glance at him in the passenger seat of my truck. He was smiling. And then it dawned on me: He had become everything I wanted him to be: a hard worker, honest, ethical and polite.

I have known Matthew since he was four years old. God had given me an amazing gift. I just saw a boy become a man, and that is a rare thing to witness.

Matthew saw a job that needed to be done. His family needed his help. Without question, without hesitation, he stepped up and delivered.

Matthew and Tim are brothers, but they are not the same.

My relationship with Tim has always been easier, less awkward . . . more natural.

Tim is instinctively courageous and confident. He can fix anything. He is handsome, tough and cool. The self-appointed defender of the weak who is always ready to push the envelope.

We call him “Fonzie.” He is everything I was not when I was 17. Just ask my classmates.

I secretly admire him, even when he pushes the envelope just a wee bit too far.

Matthew? Think Richie Cunningham. A bit more shy and not as confident. A gifted writer and artist. Someone who wears his heart on his sleeve. A model student, polite, clean-cut and destined to be anything he wants to be.

Matthew is the kid you want your daughter to date. He is funny, exceptionally smart and ready to blow the SATs out of the water.

Tim embraced me as his father almost immediately. It was not the same with Matthew.

Matt clung to the idea that his biological father and Laura would reunite. He had little use for a demanding stepfather who can lecture with the best of them.

Matthew and I clash because we are both perfectionists, dreamers, procrastinators. We are both overly sensitive and a tad needy at times.

When I saw Matthew,  I saw a mirror.

I’m stupid like that. Matthew is not my reflection. He is his own man. Whatever I could teach him has been taught. He is more than ready for whatever lies ahead; great things, I’m sure.

Happy birthday, Matthew! You are an exceptional man, and I am so very proud of you!