While it should be able to get resolved with a mature conversation, I see both sides of the coin. If you have kids and you have stuff going on, that comes first of course, but it can be a bit oft-putting to others at times. Case in point: in 2009, my grandma turned 100 and a big shindig was thrown for her. There are 20 grandkids on that side of the family (I was the 17th born) and 19 of us were there. One cousin, who rarely came to family events and has since passed, even came, but there was one cousin who didn't come because one of his kids had a soccer game, and I was like WTF? This is Grandma's 100th and you are missing it because of a freaking soccer game?? There are some cool pics from the event as well, and it always looks a little strange to see that one pic of Grandma with 19 of her grandkids (with 1 missing).