My FIL passed away early last year. Although he had been ill for some time, his death came very suddenly. He had a Direct Cremation, so there was no funeral service or gathering at the time, and his ashes were returned to the family several weeks later. Understandably, it was a deeply upsetting time for all of us — especially for my partner, their two siblings, and the four grandchildren (aged 17–22).
All of us, except for one grandchild who lives overseas, were able to be with him at the end. That grandchild found out via video call, which was incredibly hard on them.
It was agreed that we would hold a memorial celebration at some point this year to allow family and friends — many of whom had asked about a service — to come together and remember him properly. It felt like the most fitting way to honour such a loved and well-known person in the community.
Unfortunately, my partner’s siblings have gone ahead and scheduled the memorial on a weekend that three of the four grandchildren can’t attend. One is the grandchild living overseas, and the other two had long-standing holiday plans that can’t be changed. The family had made it clear in advance that this specific date wouldn't work and offered several alternative dates, including ones when all the grandchildren — even the one living abroad — could attend.
The siblings responded by saying it was the only date available (presumably at a specific venue) and added, "We can't work everything around the kids," followed by, "Well, those kids didn't do anything for [FIL] in his last weeks anyway" which I think is an incredibly cruel thing to say.
The grandchildren are heartbroken.
AIBU to think that, for a memorial, having all seven immediate family members — especially the grandchildren who loved him — should have been the priority?
Any suggestions as to how to proceed from here?