To be honest, my kids get along pretty well. I'm not saying that to brag or anything, I just think the fact that I don't discourage my kids arguing with each other needs to be put into context. So maybe someone in a different situation would have a wildly different view of things but, from where I'm standing, I think there are times you should let siblings fight.
I'm one of a whole bunch of kids in my family, and while we rarely got physical our house was still... well, let me put it to you this way: have you ever seen footage from Parliament in the United Kingdom? Yeah, it was like that. One person would be shouting while a whole bunch of other people would be screaming whatever they thought about what the other person was shouting about, and everyone was just trying to be as loud as possible in order to make their point. It was a charming kind of chaos.
I'm the oldest, so I often felt it was my duty to take things in hand and mediate disputes. As I grew up, that carried over and even outside of my family. I would often find myself work to maintain social harmony in whatever setting I'd find myself in. And now that I have kids of my own, that instinct is still very much alive and well. I've worked hard to suppress it, though. Blessed are the peacekeepers and all that, but I've come to learn that a little conflict (and learning how to resolve it, sibling to sibling) is good, not only for kids but for meddling mamas who need to let go of the idea that they are responsible for everyone else's feelings.
Of course if things get physical, dangerous, verbally abusive, or just extremely out of hand, by all means hop on in there and mom it up. But here are the times when it's OK to take a backseat:
When They Haven't Started Fighting Yet
In the past, I have been extremely guilty of pre-emtively stopping fights that I see brewing. Now, don't get me wrong: in many cases I regret nothing and would do it all over again because sometimes you have to. Like when you're grocery shopping or sitting in religious service or something. Nip that ish in the bud because things could go downhill real fast and you need them not to.
However, not every conflict needs to be avoided. Kids need conflict if they're ever going to learn how to work through it. We want things to be harmonious, but a little adversity can be a very good thing!
When It Hasn't Been That Long
When I committed myself to letting my kids fight it out, I started by implementing a five minute rule: let them shout and cry and whatever for at least five minutes before stepping in (so long as everyone's safe, of course). Being angry and upset for five minutes isn't going to hurt them any. Listening to them be angry and upset for five minutes isn't going to kill me — it's annoying, but I did longer stretches than that when they were babies, so I know I can handle it. The upside is that in that time they might be able to calm down and start to reach common ground.
When They're Trying To Work It Out With Words
They might totally suck at it. In fact, they probably will because kids aren't super rational. But giving them the opportunity to hone their reasoning and negotiation skills will make them better and better at it. Since implementing my five minute rule, there have been fewer and fewer occasions when I've reached the five minute mark. Oh sure, sometimes it goes far beyond that, but it's getting better is my point.
When You're Trying To Get More Information On The Situation
Sometimes I miss what the fight is even about and listening to them (verbally) duke it out gives me an opportunity to see what's really going on. Is my son being manipulative? Is my daughter being grabby? Are they both being absurd? (They usually are, at least to some degree.) Point is, listening to what they're fighting about and how they're fighting can give you critical information for if you do have to jump in and help mediate.
When One Or Both Are Asserting Themselves
Sometimes what sounds like an argument is actually one sibling refusing to put up with another sibling's sh*t. This is a good thing. Yeah, at some point they're going to have to learn to assert themselves in a less abrasive manner, but every now and then they're probably going to have to establish their autonomy and demand respect in a way that only their sibling will understand: screaming. And, honestly, sometimes it just feels really good to stand up for yourself and I feel like that feeling is worth a fleeting moment of unpleasantness.
When It's Been Building For A While
I don't know if it's moon cycles or something in the water or whatever but, sometimes, tensions are building and will not abate until everything comes to the fore, siblings get a solid fight out of their systems, and then they can go back to normal. No fighting the moon, lady. Let it happen.
When They're Both Being Jerks
No need for yet another person to be bogged down in all that negativity. Let them be miserable together.
When It's Funny
Put it on YouTube. Monetize your channel. Get rich.
I kid... but, like, maybe secretly film for posterity. Someday they'll laugh at it, trust me. My mom filmed some of the (few) fights my brother and I had and it is hilarious. Honestly, I treasure those videos because lol wut?!
When Their Fight Is Giving You Some "Me Time"
I've leaned into it. Because when my kids are shouting at each other they're not shouting at me to do stuff for them. I've gotten so much reading and uninterrupted chores done, you guys. It's magnificent. It takes a little while to learn to be OK but at this point I'm very good at making myself a nice cup of tea and just tuning it out.
When You're Just *Done*
It's OK to just be over it. Maybe you've had a long day. Maybe they've been nonstop for just too long. Maybe there are other things that require your energy right now and you really can't be bothered with making this specific instance of reasonable unpleasantness better. They'll be fine on their own, even if they solve nothing and just stay angry at each other. It won't last forever.
If You Think They're Secretly Wizards & Will Start Dueling
I mean, I've sort of given up on the idea that I'm ever going to get my Hogwarts letter, but I live in hope that my children might someday see an owl fly to our house.