Holidays would be so much easier if they took place around a photo wall of all of us when we were young and lovable.

This has been my theory for some time now, and I’m sure I’m right. Definitely.

Try this out. Think about the relative who annoys you most. We’ll call him Uncle Harry.

Maybe Uncle Harry always feels free to comment on your weight or receding hairline. Maybe he always gets your name wrong and reprimands you for having changed it when you correct him. Or he misses your every visual cue telegraphing just how much you couldn’t care less what he thinks of the president. Ever.

The plastic wrap isn’t even off the cheese ball yet, and he’s already Hoovering all the oxygen out of the room. His lips begin to move, and the soundtrack of Christmases past torques around your head. Let’s say it’s the title track to “Jaws,” just to get us all on the same page here. He starts talking, and visions of harpoons dance in your head.

You aren’t proud of this. As we all know, shame is another hallmark (little h) of the holiday season.

Now, here’s where the photo wall comes in. Just when you’re about to say something your mother is going to hold against you for the rest of her days on this earth, you turn toward the wall, and there he is: Uncle Harry, age 4. He’s a mop-haired little doughboy, and he looks as if he’d rather have his fingers severed from his hand than stand still for the camera in this black-and-white picture, dated 1942.

You lean in and squint at the caption: “Harry misses his fighter pilot daddy. Merry Christmas, honey.”

Tell me you’re not going to see Uncle Harry a little differently. Maybe even peel off the cheese ball plastic wrap yourself and say, “No, no, Uncle Harry, you first.” You’re fighting tears.

I’m speaking from experience here. The time-travel photo wall works.

It can get you through almost anything. It’s multi-seasonal, too.

We have one on our second floor, and I can’t tell you the number of times I’ve walked over to that wall after a debate with my husband about professional attire. There he is, age 5, dressed for his college graduationin a red blazer and tie, his hair trimmed to a quarter-inch stubble.

In my experience, this is the last time he has looked so tidy. So ironed. So totally dressed by his mother.

Hashtag: #NotMyProblem.

Now, this photo wall strategy won’t work for relatives who you think should be in prison. Understood. We’re talking about the people in your life who may be gnats on your shoulder in April but become your personal beasts of burden when December rolls around.

Which brings us to you, my friend. Specifically, you and that mood of yours.

Let’s all try to remember that nobody wins if we don’t all show up with our A game. To expand on that sports metaphor for the first time in my life, ever: There’s no “i” in team, but it’s definitely there in the word misery, so you pick. You can be part of the Yuletide coalition or lead the mule-train slog to a relative’s Facebook page. We’ve all seen that nasty holiday post, and it haunts us. How could anybody say that about a family member? And that picture. My Lord.

I end this with a reminder to my own family that I once was young and adorable, too, and I’d appreciate it if you’d think about that before complaining about how many times I play Bing Crosby’s “Mele Kalikimaka.”

Think of me at age 7. I’m a giddyap-and-go cowgirl with a fringed skirt and dreams of owning her own dude ranch.

So sweet. Shy, even. Back then, you couldn’t beg an opinion out me.

Go ahead. Laugh. Get it out of your system.