What would you have done ?

It's interesting that your husband seems to side with his sister on child related issues more than you. Have you talked about how you will raise your children as I can see a clash of parenting styles ahead if you haven.

I would be very clear with her that I think it’s very entitled for her to be asking for expensive gifts for her DS knowing that her kid has broken the cot and she hasn’t offered to replace it. I would also state that your DP’s FIRST priority should be to his own kids, not hers.

The real issue seems to be that you are resentful of the financial support your husband provides.
If you have a very reasonable/high disposable income I think it's nice your husband treats his nephew who otherwise might not get these things.
If you don't have a reasonable disposable income it sounds unfair.
I think it was up to your husband how the cot situation was managed. If it was me I'd probably be pretty upset if my OH went over my head on this.

I think now you’ve established the situation I would not go backwards. It would be totakkg justified to be nice but equally to read him the riot act on arrival. Your house, your rules

Definitely getting the picture. Wonder how other people put up with her attitude.

Absolutely so.
Inane behaviour for a 10 yr old.

When my son was a teen, he had a friend that he used to get 'silly' with-they would set each other off.

{at 14}
I heard splintering wood, and went to investigate- the side panel of son's Pine bed had completely been kicked in.

I couldn't prove which one of them did it though, and neither owned up {at the time.}

It was a karate kick, and son doesn't do karate.

I had to let it go and buy a new bed- but since found out that cheaper timber used for children's beds is less structurally sound.

It's quick~ grown in Northern latitudes and very sappy. Had it been Victorian, the kid would have broken his foot most likely!

Obviously It was very annoying- got a replacement from Ikea that was affordable. .

Yes they do, but so does stupid behaviour, At 10 he should know better than to do something that will break a baby's cot.

if my TEN year old broke a baby's cot then I'd apologise a LOT & offer to buy a (new, not one of market place) cot.

I agree with you OP.. Nephew is 10 he's more than old enough to know that a kid of his size is going to break a baby's cot simply by standing on it let alone jumping on it. Why is this kid not being taught to respect other peoples property? Its like the kid and his mother are hanging on to the attitude of its ok Brother/Uncle will just splash the cash to buy another. Having read your replies I'd not be putting a penny toward the kids new technology and telling the hubby's sister sorry there's now a cot needs replacing due to her son being careless and breaking one so now she can save up and buy her kids stuff herself rather than rely on handouts from her generous brother for once. The sister sounds spoiled and entitled and unfortunately shes raising her child to be just as entitled as her. I'd honestly put a stop to financing her so much and make her pay for what her kid has damaged

Omg 🤦‍♀️
She doesn't 'hate' the 10 year old but she is rightfully pissed off for his irresponsible mothers attitude to him disrespecting her house and furniture!
If anyone let their child break my stuff like that and seemingly not care I would lose it big time.
What is with these responses

Why do you have so much hatred for a 10 year old?
You only ever refer to him as SIL DC or DH's DN - never your nephew!

You have DC of your own now - I can guarantee that at some point they'll break something of someone else's and you'll realise how shitty you've been towards a child!

DN sounds like a nightmare. Does he break things at home, school etc? Something just doesn't sound right here, with either the child or your DH attitude to putting up with it.

This…how are people justifying a TEN year olds behaviour???

What?

The issue is with the SIL AND the husband. No one is trying to “drive them apart”

Husband should have spoken to his sister after his wife asked him too. The SIL should then have replaced the cot. It didn’t need to be brand new.

I don’t understand your point.

OP: yes. It should have been brought up with SIL by your HUSBAND! And she should replace it using pocket money from the 10 year old.

Dont listen to grumpygrapes nonsensical comment.

I’d have been annoyed and I would have gently mentioned it in a non confrontational way to DSiL either straight away or at a point in the future, but would have accepted to have needed to buy a new one myself. I would not have asked for money (but would have eventually accepted any offered).

Accidents do happen with kids all the time and yours later may have an accident at theirs (older DN and more expensive toys with yours being younger and less aware).
I haven’t read all the replies everywhere, but if DH is thinking of buying DN a PS5 I feel that a bit expensive gift.

It's taken a while to get to the root of the problem, because you clearly don't operate your finances in a usual family way, so people couldn't wrap their heads around what is happening.

The way you operate your finances is, well, wrong.

The problem is entirely how the two of you are viewing your finances.

Your DH is not giving HIS money to help his sister, he is giving FAMILY money (ie yours too) to help his sister without any consultation with you.

You are married with children. You are a team with invariably one party doing more of the childcare and thus not earning, and one party working for money more. Therefore, all money earnt is both of your money. You pay the bills and food from that and your children's stuff first. (It doesn't have to be a joint account, just the principle). Then the remainder is split 50/50 as disposable income for both you and your dh. Your dh is welcome to spend that on his dn, that's his choice.

If your dh is making unilateral decisions on spending money that you don't have out of a joint account, then you are in a very unhealthy sexist relationship.

The real problem is your grabby SIL then, and your DP’s pattern of giving her whatever she wants out of your family pot.

I would have sat there open mouthed if BIL said that to me about my partner. He acts the same way but hasn’t had the front to say it out loud! I understand your fury now.

Blimey OP the more you post the more it sounds like a huge DH problem and definitely not petty, more like the straw the broke the camels back. Honestly poor you. The SIL sounds horribly entitled, the nephew runs riot in your house, DH is a pushover buying him expensive stuff that he can’t really afford without it impacting his immediate family. Madness. I still don’t think making it about the broken cot and approaching SIL and asking for the money was the right approach because it’s just stirring things up in a way that’s unlikely to help but I would be having it out with DH because the wider situation is completely ridiculous.