This little guy evidently did something to antagonize his adult buddy in the home. Apparently, the big guy bit down on his head - ouch. He didn't crack it like an egg, but close. His owners found him with a severe nose-bleed, a few puncture wounds, and the top of his head puffing in and out when he breathes. Here's a link to the video.
I had hoped it was just a puncture to his sinuses, but his nasal bones were broken and caved in, as well. Every time he breathed, air was puffing under the skin. We also found that the muscle and periosteal membrane (that covers the bone, usually), were stripped away from the top of his skull. There were big blood clots over both eye sockets, as well as in his nasal passages. You don't want to see that picture.
We cleaned things out, and put him back together (pretty much - there were a few things we had to toss out). He looks pretty "Frankenstein-ish" in the post-op picture, and you can see there's a lot of swelling still present. Even though this doesn't look so great, this morning he was up, and willing to eat and drink. Hooray! We sent him home on antibiotics and more pain medicine, and I think his prognosis is pretty good.
You can see in this video that he is feeling much better, even though he doesn't look so great.