EX/ Pil's and care for DS

[Ivedunnit]

Ok need a sanity check.
Myself and ex and DS (12) live in another country to EX PIL's ( who are lovely genuine people).
Our son spends 50% of his time with both of us and we alternate weekends.
I called ex yesterday with regards to him taking my son in two weeks time on the Thursday night as I am getting a new boiler fitted and there will be no heat in the house. Till late Friday. ( New DP is fitting boiler - ex is unaware of new DP) I also have plans for the Saturday evening ( this is my weekend without DS).
He informed he me that he won't be around that week as he has to go see his parents for the week. His dad had a mini stroke two weeks ago, they are both 87.
His sister is going away that weekend and his brothers wife will be in hospital that week. So there will only be his niece at home to mind the PIL's.

I think I am pissed at the assumption I should just be able to cover his weekend with no consultation.

AIBU

Altinkum the agreement is 50/50 but thats not how it actually works.
As my ex works shift he works 5 days out of 10 in a fixed pattern he should have our DS on all of his days off. But this is not what happens. Typically he has DS 3/4 of his 5 days off. This always changes.

Anyhow I do agree I am BU!
When we got news of his dad being ill I offered to pay for flights home etc but this was refused.
The issue for me is the communication and the assumption that I will pick up the slack with no consultation.
I'm not typically an unreasonable person honest!
Thanks again to everyone!

What I am trying to say is .... Why would anyone feel put out about having their child with them. Yes feel annoyed that an ex doesn't see your child regularly as this can cause psychological damage to your child. But why feel put out that you have your child on your weekend off. I don't understand it. Why feel your ex should have your child when your child's grandparent is very sick. Perhaps I'm odd but I don't get it.