To be really worried about marbles around DD1

I choked on a marble when I was 4 so yanbu. I was moments from a tracheostomy when the marble thankfully dislodged.
If your ex won't listen to reason I would put something formal in writing/ email and include the safety guidelines linked above.
If you are in the process of negotiating custody arrangements you could also let your solicitor/ mediator know.
When I was getting divorced a friend advised me to treat every communication as it would be read aloud by a judge at some point. There was never any chance of us ending up in court but I found it was a useful reminder to have in my head about how to approach all issue - clear, focused, evidence, no emotion.

I have an older son (7) who's loved marble runs since around age 4, youngest son 1.5 yrs at the time. I would always FULLY supervise and count every marble after we had finished. I removed the marbles from the box and placed them in a jar in a high up cupboard whilst not in use.
Ball runs are another alternative.

YANBU. Marbles are a minimum 3+ kind of toy and I am generally pretty chill with that kind of thing / ages of toys within reason. But this is a risk and he is failing to basically parent your child safely, especially when you have already informed him of the risks before.

@TY78910 read the OPs posts. She's divorced and the dad lives with his parents. It's their house that has the marbles and OP can't be there to supervise. The dad not giving a shiny shit about his toddlers safety means he can't be trusted to supervise properly.

Also adding that when selecting that gif I had no idea it had a caption. I just meant the guy blinking 😂😂😂😂😂

Me half way though this thread (gif)…

on to the actual subject. DD1 fell in love with marble runs as they play with them in reception. She’s 4. As far as the older DC is concerned that’s an ok present.

On to how you feel about it near your youngest. Just keep it in an area that DC2 doesn’t go in to and it can only be played with there.

In all honestly my DD has been gifted all sorts of bracelet sets with about a million little beads that go all over the floor, Barbie’s with thousands of mini accessories and other tiny random crap. I was worried about it when pregnant with my second but it’s actually (touch wood) fine. We don’t leave them unattended so we always intercept when something small is picked up (which is rarely as we say to only play with that stuff in DDs room). I do think you’re being a tad too cautious

That's bad. Someone I know, her husband choked and died from food. Imagine a child with an object

I have a similar age gap and I bought elder DC a marble run. I always supervise him with it (the marbles are not accessible to him without asking) but we also did lots of work on the importance of packing the marbles anway and making sure his younger DC doesn’t get them, and it’s been fine. In fact it’s been helpful because now if he sees younger DC with anything small like that (such as Lego) he alerts me.

I have a marble run in my classroom and so many parents comment, “Oh Flossie loves the marble run! We can’t have one at home because of younger sibling.” I hear this from nearly every parent with a younger child! You are not alone.

I also keep the marbles in my desk and hand them out one by one and count them back in, because they go everywhere!

Get rid, and have no regrettes

A nursery would not allow a child of that age to be around a marble due to the choking risk. However it doesnt sound like your DH is likely to listen to you .

You'd be unreasonable to not worry! I'd think it was common sense that babies and toddlers don't play with marbles.
You should be able to speak directly to your ex and have him take it on board. It doesn't sound like he will though. In your situation I think I would casually mention to the ILs that 1yo is putting a lot of things in her mouth so you are keeping small objects, like marbles, out of her reach. That may prompt them to take some action. My DN used to come to mine for contact with her dad, if her mum had approached me with a concern like this I would 100% support her and take steps to keep the child safe.

We got a marble run for our 3.5 yo, but he's not allowed to play on his own and generally we try to use it when his little sister isn't around. We keep the box out of reach, and count the marbles every time.

She did stop putting them in her mouth very quickly, but I wouldn't even trust my 3yo not to do something stupid with it!

You’re not even slightly unreasonable, op.
I’d be very unhappy indeed to discover I was married to such an imbecile.

Chad valley marble run is from age 3, so not appropriate for a toddler. Can you trust the adults to supervise?
I followed your previous thread OP, so I'm not so sure.

Not unreasonable, she could choke. Can you speak to in laws as it’s in their home? DH sounds unlikely to listen.

Ds3 got his first marbles last year for Christmas (big Marble run). He was 7.

I wouldn't have them in the house with a toddler.

I’ve got a marble phobia. I can barely even look at them as all I can see is them getting stuck in throats. I could not have one in the house so I agree you are defiantly not being unreasonable

Im not sure if youve explained how theyre playing the game- but similarly to above any older kid game that my DD wanted to play had to be at a table under supervision or during a nap to prevent small hands catching marbles/small bits etc. and shoving them in mouths/noses/ears.

Another NHS one. If he doesn't take you seriously, get the health visitor involved.
https://www.betterliveshealthyfuturesbw.nhs.uk/learning_resource/safety-preventing-choking/

Would he listen to an authority? It's literally in the third paragraph. He's an idiot.

https://www.nhs.uk/baby/first-aid-and-safety/first-aid/how-to-stop-a-child-from-choking/