Dh’s mum slapped ds

Because that was 43 years ago and when we know better, we do better.

Why not?

Wait until emotions have died down - but I would be seriously unhappy about this and would want it discussed and an apology given. I would also be very wary about leaving toddler in MIL's care if she is so reactive. Three year olds do scream, it's hardly age inappropriate or surprising behaviour. You just walk away if you can't cope with the noise. I would be more understanding (though still upset) if an adult hit a 3yo as an automatic reaction to being hurt themselves. To do it as a conscious choice to try and "snap them out" of a tantrum is inexcusable - that hasn't been accepted parenting advice for about 50 years.

It is illegal to hit children in Wales as well as Scotland. Hopefully England will catch up soon (sorry, I can't remember what NI's current ruling is!)

How do you find your MIL in general, op? Have you ever had any minor reservations about her attitude towards your son?
It's just that something like this episode gives you a very concrete reason to draw boundaries. Horrible as it was, it's now your negotiating tool and justifies whatever you deem fit in the future.
I'm projecting a bit but I had issues with my own mother and didn't much like her looking after the kids but couldn't really give a good reason as to why. There was nothing tangible, more that she can be quite emotionally manipulative and I was (still am!) always on the high alert for her doing this to my kids (now older teens).

I'm not sure we're holding up Penelope Leach and her water in the face method of dealing with toddlers emotions in 2025.

Anyone who's first instinct is to lash out and physically reprimand a child, under any circumstances, wouldn't be within arms reach of my DC. I would ring her and say that you have been thinking about when she slapped DC the other day and wonderiing how to bring it up, as it's been really bothering you. That you want to be very clear that it can not happen again and you would like her agreement and reassurance that it won't. And then not leave DC unsupervised with her again.

Please don't feel guilty, op- you were more concerned about checking your son was ok in that moment- which is totally understandable.
It's such an unexpected thing that you processed it a bit later, and realised this is not ok.
So, yes, as others have said, you and your husband now need to address this with his mother.
But don't go feeling guilty now! This is on her, not you (and posters trying to ramp up your guilt are not worth any head-space)

Please don’t question your very visceral reaction to this incident. Slapping, hitting, even giving a little shove is a ridiculous response to a child having a tantrum. It’s as if the child’s emotions about whatever triggered the tantrum don’t matter as much as the person’s desire to shut them up. I would be very very pissed off if anyone did this to my child and I would not let it go. Really unacceptable behaviour.

I dont know what country you are in but in Scotland she has broken the law by slapping your child

I wouldn't be allowing her anywhere near my child again if I'd seen this. Or at least until there had been serious discussion with her involving your H and yourself and she showed that she had taken on board that physical punishment is assault and she agreed not to do anything similar again.

You definitely need to approach her about this otherwise she’ll think it’s acceptable and perhaps do it again. Speak to your DH and hopefully you’ll have his support and both talk to her together.

When my 3-year-old (now 47!) had screaming fits I followed Penelope Leach's advice and sprinkled cold water on his face - this works, amazingly. I am not sure thumping someone on the back will stop a tantrum (left my DD in the deli aisle of the co-op superstore when she threw a tantrum once - I hid behind the nearest shelf unit so I could see her but she couldn't see me - when I was not watching she stopped screaming, remarkable!) as it's more attention. Ignore tantrums unless there is physical danger.
Get DH to explain all this to MiL.

You definitely need to bring this up. As another poster said, if she did this in front of you I'd be afraid of what she'd do when a parent isn't there. I'd be prepared for your DP to play it down, he may think it's not a big deal if he grew up being slapped. I'd absolutely limit contact with your mil if she apologises,if she doesn't then no contact.

I probably would have slapped her to be fair.
Hiting a child never works or is constructive in anyway .
Positive reinforcement and encouragement.

She sounds like she has a short fuse herself but doesn't have the excuse of only being 3.
Needless to say I wouldn't trust her with a child alone

You're completely right to be angry about it. You don't say if she is still around or you are on holiday together or whatever. I would simply find a way to get her on her own and tell her calmly and factually that she is not to tap/smack/slap your child again. It is not her place to do so and you and DH will discipline your children as you see fit. You recognise that it may have been reflexive and also perfectly acceptable when she had small children but it isn't any more so she needs to contain her inclination and remove herself from the situation if your DS is pushing all her buttons.

I would not be accusatory about it. Ideally you want a conversation which if she takes dire offence to and decides to kick off to your DH about, you can say that you did not want to make a big thing of it as a once off and respectfully asked her not to do it again. The worst thing you can do is put your husband in the middle of this when you need him to be on the same page as you.

I also wouldn't make him have the chat especially if he wasn't there. If he was, he's quite likely to have barely noticed if she was quick to lay out smacks when he was a child. Better to have the chat and ask forgiveness later if needs be.

Bring it up.
Talk sensitively about it.
Discuss how you would like MIL to react in future, though if child, say, all of a sudden bites Granny, she might instictively protect herself again.
With the shock of the screech and the shock of the whack I can see why you also were shocked into silence.

It seemed almost like a defence mechanism - in defense of her ears..

I would not leave small children with Granny alone until they can talk and behave more like a school boy.

She simply wouldn’t see my child again. I would have absolutely said something at the time- you need to be an advocate for your child.

My MIL thinks smacking is acceptable. I do not. Before we had DC and she said there's no issue with smacking FUTURE DGC, I kindly reminded her that "anyone that smacks my children, will get a smack from ME". She has never as so much raised her voice to our 3 DC. Unacceptable and she needs to be told!!!

You really need to speak to her about this to tell her how unacceptable this was. She has no right to slap your child. What does your husband say about this?

My mother slapped my son in front of me once during a meltdown. I cornered her and told her to keep her fucking hands off him or I'll be the one doing the slapping.

A mil wouldn't be any different but I get in the shock of the moment sometimes you freeze.

You can still stick up for him and that means an uncomfortable chat with your bloke at your side doing the talking.

Her instinct was to hit your child?

I wouldn't allow her near me or my child again honestly.

Your dh can still have relationship with her, you and your child don't have to be involved.

No one who thinks it's appropriate to slap my small child would be seeing them again in the near future.

I'd be furious and having very stern words. Don't keep quiet or she'll do it again.

You need to have stern words with her, and tbh, I wouldn’t be leaving my child alone with her, ever.

If it was a slap (rather than pat to get his attention) you absolutely have to raise it. He's your son and needs you to protect him. Your MIL needs to know that she is not allowed to raise her hand to your child again if she wants a relationship with him.

Understandable that in the shock of the moment you froze. You need to have the difficult conversation now though and make it clear that it’s unacceptable behaviour and it it’s made you wary of trusting her around him. Next steps then based on how she reacts.

Fucking hell. She needs to control her Anger.
Even if DS wasn't hurt physically, he would've been shocked and quite likely will be frightened to see her every time
Nasty bitch. Tell her bluntly that if she ever does it again, she will not be able to see him unsupervised again.