[c312]

It's his kid, therefore, its his decision. He could have told your dad in advance, but think how that would sound if you told somebody that you don't want your kid to watch R movies at this friend's house. That's assuming that the other parent lets their kid watch them and that it is bad parenting, that would be very awkward for the other kids' parents when you think about it.

Nowadays, I would never show a kid a film he wasn't old enough to see unless his parent said it was okay, it's just common courtesy.

That being said, I think the kid's dad should get over it, SPR is a good exception to make, it's not like it's R cause of titties and zombies and stuff like that, it's accurate and it's historical but still, it's the dad's call.