So I thought there was this book about ritual burial at the undertaker's house. And if I remember correctly Orcs were celebrating their death rather than woe. Those crying and unhappy would be executed or something.

But then we have this sobbing orc mourning his brother just outside the village. Not a very canonic behaviour, right?

I found that odd but maybe I remember it wrong.

I thought there might be something to it too, but neither reading the book nor having it in my inventory seemed to add any new dialogue options. Maybe Larian had plans for the book that went unrealised, or maybe it's just a joke.

Perhaps it's just so the player can feel justified in killing him and digging up his brother's corpse. :)

His brother’s two piece’s of unique armor make killing him a must in my book, normally I'm not so heartless in RPG's, but the armor is too good to pass up. I let the two handed melee chick use the armor at low levels and give it to my rogue once better metal stuff starts to drop. You just need to make sure your rogue has 8 strength before you hit level 5-7.

You actually can get the armour without him bothering, I found it in a grave - next to the totem on the utmost left - far away from his view sight.

I would have loved to have a dialogue choice confronting him with the aforementioned book passage but alas I just decided to leave him to his sorrows... while stealing the armour.

His brother's grave isn't marked only way to find it is to convince him to show you where it is. Once you know then future games I guess you could sneak in and get it but the first time you need him to go there and show you. You get two matching pieces of unique armor when you find it. Not a set but they match visually.

Oddly I found them without interacting with the orc. My "girl" just had enough perception to find the grave next to a totem.

There is no totem near the brothers grave, the three totems on map are near three grave sites, but those aren't the grave site for his brother. Just posting this so other readers don't go nuts looking for a totem marking the brothers grave.

Okay, if you insist I'll double check. I wanted to start a new game anyway.

Are we talking about the unique Orc helmet and armour (with +5% fear)?

I no longer have the armor to look at due to the level of my characters now, but I remember it had high resistances for all 4 elements 10%-15% each I think, one of em might have been 20%. One piece gave +1 strength the other +1 perception, but I don’t know about the fear, I don’t recall seeing that. When worn, the helm had two large horns displayed and one of the shoulders on the armor also had two horns.

No need to start a new game I ran down to the spot in my game where I dug him up to double check, no totem around the site for sure. You can run to the spot in your game to check if you’ve dug him up, if not talk to the orc about where exactly the grave is. You need to win a rock paper scissors game I think. He’ll run to the spot after you win and simply dig at his feet.

Ah okay, you are right. It's close those torches, I mixed them up with the totems.
Nevertheless my "girl" spotted the grave with perception 10 without the help of the orc and without him noticing.