This is going to be long but think I need to post the background
I've posted previously about SIL's wedding. I have 3 DCs - age 3, 2 and 13 weeks. The oldest have just turned 3 and 2 respectively so still small.
SIL is getting married about 150 miles away on a week day. We have been told no DCs at the wedding. Mil has a difficult family background and her half-brothers children will be going however - albeit they are older than ours. I susir t ultimately that SIL will also permit her friends to bring small babies. I understand that it is SIL's wedding but I find it pretty hurtful that our children (who are actually her closest relatives) are to be excluded.
My parents are extremely supportive of us and will normally drop anything to help us out. Mil has form for being very difficult and has been very unhelpful at difficult times - eg looked after putt DS on the day of my grandmother's funeral (250 miles away) but refused to rearrange plans so I had to get out cleaner to come and look after DS (then 1 year old) as she had to leave at 5pm. The whole thing was horribly stressful and I still find it very upsetting to think about.
My parents normally drop everything to help us but normally go on holiday with friends around the date of SIL's wedding. They therefore told me immediately that they may be able to look after our DCs but that - in this instance - they actually won't cancel their holiday if the group of friends can only manage that date (they are all retired so tend to go quite last minute to get the best deal) and we should therefore get a plan B. I immediately highlighted this to DH and his response was - (massively fucking entitled) oh it's my sister's wedding. Surely they won't go away. I said they very well could and he should highlight this to his family now as we may not have any childcare and ultimately I wouldn't be able to go. Plus, I could very well still be feeding youngest DC. Really the only option would be to take someone to look after the DCs on site and I didn't even know if that would be feasible. But I was highlighting it now so that there were no amateur dramatics near the wedding if I couldn't go
Communication within DH's family is pretty piss poor so nothing was done.
At the weekend, SIL, MIL and FIL came ti visit and stay the night. SIL said something in passing about my parents looking after the DC and I said that actually they maybe away and there wasn't really a plan B. I said that I could perhaps ask my DS's key worker from nursery to travel to the wedding and look after the DCs but we would need to get him accommodation. And, in any event, I was uncomfortable about being away from my youngest DC even if I could get someone look after all DC at our house.
SIL told me that there were no rooms left at the hotel but if I got the key worker, he could perhaps stay at a local B&B. That she was having to lay £150 a head per guest and she wanted me to be able to relax and enjoy myself and also keep costs down - hence why our DCs weren't invited. I said that the best solution maybe to ask the key worker. And, if I did, would SIL like the DCs to be brought to the church (waiting outside during the ceremony) for a few photos as they would be in the area. Totally up to her obviously but thought she might like it. She said yes, but she was banning children from the church. I said I quite understood as FIL's brother's children had made a terrible racket during ours in the church (MIL insisted they were invited) and you could even hear the noise on the wedding video. MIL said she couldn't remember that but I said (nicely) that it was on the video. I also said that if my parents were looking after the DCs, they had also offered to bring them to the church (to wait outside) and take them home (a big thing as a huge drive) after if she wanted photos.
So - it was all perfectly pleasant and I thought the childcare issue was clear. More importantly, there was actually communication like normal people. DH then went to work in the morning and the DCs and I went out with SIL and the PILs for brunch - all perfectly pleasant. Nothing else said. I was slightly nervous about going out as the PILs had been invited to visit DC3 a few days after she was born and had been very late (with no communication). I was upstairs feeding the baby and DH had said something to MIL about it. She had started shouting and bawling at DH saying it was my fault 
and I was manipulating them and being very rude about me. I decided the best thing to do was pretend I hadn't heard and gloss over things. But, again, everything perfectly pleasant at brunch
DH then arrives home and asks me what I had been saying to his sister? I explained the position about childcare and said that I had highlighted this to him already but his approach seemed to have been that my parents would have to just cancel their holiday. That wasn't very constructive so I had highlighted things to SIL so she could make ab informed choice about allowing the DCs to attend in the vicinity and be looked after off site (pretty pissing annoying that DH could have mentioned it earlier so we could have got a room for them and carers at the hotel but now we couldn't) as ultimately if we couldn't get appropriate childcare, I wouldn't be able to go and with a wedding of 60 people, that would be noticeable.
DH then says that obviously I had a chip on my shoulder about FIL's neice making a racket during our wedding and that my parents were manipulating things by refusing to cancel their holiday (the irony after my grandmother's funeral and various other times that they have dropped everything and driven 300 miles to help us out after the PILs have let us down!). I susir t he had spoken to MIL on the way home.
I am absolutely fed up with this. I am fed up of rather than everyone talking civilly about things (as I tried to do) and resolve problems in good time, MIL then approaches DH behind my back. If she or SIL had a problem, why not discuss it with me at the time or the next day? I am fed up (and I think this is the crux of it) if DH not simply explaining that all I am trying to do is sort out childcare for the DCs (as basically he seems to have opted out of it and my parents - his indentured servants obviously - are to drop everything AGAIN to help out). Why is DH not able to actually support me (his wife) and make it clear - politely - to his family that if you have your wedding hundreds of miles away and don't invite your very young nieces and nephews, then yes, childcare will be an issue and that is not bring "difficult". It's a matter of fact. And, actually, if your "keeping costs down" banning your brothers children whilst letting others attend is actually pretty fucking hurtful
I actually don't know what to do. I've said tinDH that I think that actually everyone should just be honest and communicate clearly with each other now. So if he thinks my patents are "selfish"
and "manipulative" (the breath taking cheek!) he should say to their faces. Further, I will contact SIL and MIL and ask them if they need me to clarify anything about what we discussed. Further, another option is for me to not attend and look after the DCs which I think maybe the best option all round
I'm actually so so sick of this. I don't want to see the PILs again and I don't particularly want to see SIL again.
Should I contact them? Should I just decline the wedding invitation? I want to make it clear why
I also need to sort out the DH issue too