We often underestimate just how much our pets notice the small, everyday things we do.

One dog owner, who used to spend hours playing their Nintendo 3DS before taking their dog on a walk, was surprised when firing up the console after a long break triggered a sweet, unexpected reaction from their furry companion.

Read on for this heartwarming story.

My dog still remembers the sounds a 3DS makes

My dog is 11, and I’ve had him since he was around 9 months old.

He was my first pet outside of college and as a “real adult,” so we would do everything together once I got home from work. This would have been in 2014.

He’s reminded of their old daily routine.

One thing we would do “together” is sit in my apartment bedroom while I played on my 3DS, which was brand new (to me) at the time. We had a routine going where I would play for 2 hours or so, close the system, and take him for a good 30-minute walk around my complex/neighborhood.

The dog soon began to associate the 3DS with going on a walk.

It got to the point where my shutting the clamshell down and the 3DS hinge snapping became a Pavlovian response; my dog would hear that snap, stop whatever he was doing, and head to the door for me to get his leash on.

It’s now 10 years later. I’ve gotten married, moved across the country multiple times for my job, had a kid, and mostly put the 3DS away to make time for other things. The last time I might have played it was 2016 or so.

Things have changed now — for both of them.

My dog is now an old man, much slower than he used to be but still very sweet and loving to not only me, but my wife and daughter.

His back legs are stiffer, he’s got white fur on his face, and he seems to have trouble hearing certain sounds that used to not be a problem.

But when he opened up his 3DS again, it was like the old days again.

A couple of nights ago, I found my old 3DS while cleaning out a drawer. I got it charged back up and decided to play on it a bit after the wife and kid went to bed. My dog took a nap right next to me as I did so.

After an hour or two, I decided it was time to call it a night and closed the system, the hinge making that same snapping sound it did years ago.

And just like those years ago, my dog woke up from his sleep after hearing that snap, looked at me for a minute, wagged his tail gently, and then laid his head back down.

We’ll go on a walk around the neighborhood tomorrow.

Oh, the halcyon days of the Nintendo 3DS.

Redditors are sure to get a kick out of this one.

It’s surprising just how well dogs catch on to things in their environment.

Sometimes wardrobe changes can tip them off.

This commenter feels like this story was written just for them.

Pets can have incredible memory.

It’s heartwarming how such a small sound can reconnect a pet and their owner in such a delightful way.

Dogs really do make the best friends.

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