Summary
Baldur’s Gate 3contains an easter egg that references Gorion, the mentor and father figure of the protagonist (Gorion’s Ward) of the original Baldur’s Gate and Baldur’s Gate 2: Shadows of Amn.
If you’re in the mood for some light grave-robbing, the various mausoleums of the Graveyard in Baldur’s Gate’s Lower City could prove fruitful. One such area is Gorion’s Mausoleum, a reference to Gorion but not actually related to the man himself. Instead, the mausoleum holds the body of Lord Gregorian Gorion, an individual hailed as the first high constable of Baldur’s Gate. This is likely a nod towards Gorion’s Ward being the protagonist of the first Baldur’s Gate game.

Such Heavy Bones You Have
However, an interesting thing about the right honourable Lord Gorion is just how much his skeleton weighs. As pointed out in a Reddit thread byQuegurjin, the skeletal remains of Lord Gorion weigh 500 pounds. This weight suggests Gorion has the most dense skeleton in existence, over 50 times heavier than regular skeletons and at least twice as dense as the densest material in the world, which is osmium.
There are a ton of people who have exceeded 500 pounds in weight, but that’s because of their large amount of fat and/or muscle. To weigh 500 pounds when you strip everything away from the bones is beyond the realm of possibility… except for Lord Gorion. The first high constable of Baldur’s Gate must have weighed over 1000 pounds in life, and likely protected the city by throwing himself around and crushing interlopers to death.

The weight of this skeleton also makes the prospect of stealing it more tricky. It’s a completely pointless endeavour, of course, but we all know someone who enjoys collecting and curating a corpse collection back at the party camp. Personally, I like to store them close to wherever Gale happens to be sleeping.
To amass enough carrying capacity to hoist Lord Gregorian Gorion, one must have a minimum of 21 strength. If you want to carry anything else besides Faerun’s densest man, then you’ll need an even higher score.
In the end, the best deterrent to grave robbing is a really heavy skeleton.