I'm not going to answer any of your questions, just offer some thoughts and more questions.
When you start the sentence "does it matter..." it sounds like it DOES matter to you. And that's fine. You don't need to hide it.
Have you ever regretted attending a funeral? Or a family event? If so, was it because of what you missed or because of what occurred at the event?
Who else will be there? What are the unwritten expectations in your family for these events? Does MCF need to attend? Does he want to/do you want him there?
How does your vacation figure into this? Is this a weekend trip or a 10 day vacation that you have dreamed about for years? Can it be rescheduled? How significant is the financial component--and I mean to your life, will it affect savings, ability to take another trip, etc.
You don't need to answer any of these questions here or to yourself, but it might help make things clearer.