Sons of the Forest respawn mechanics have both enemies and items return when the game is reloaded, but not your companion allies. The system by which elements of Sons of the Forest respawn and come back into the game isn't an obvious one, nor does it appear to be wholly consistent and predictable, but there is a logic to it (of sorts), in what you can expect to return to the game. We'll explain the Sons of the Forest respawn system as it's understood at time of writing, how it plays to your advantage, and what its limitations are.
Do items respawn in Sons of the Forest?
Yes, items in Sons of the Forest do respawn, even those that you would normally expect to lose permanently, like certain special weapons. Respawns occur on closing and reopening the game, whereupon the world at large tends to reset. Your personal inventory and storage should be fine, as well as your base modifications and constructions, but everything outside of your additions goes back to factory settings, with items and resources respawning accordingly (at least at time of writing). It's possible that these rules may be altered in the future with further updates - but they haven't yet.
Do enemies respawn in Sons of the Forest?
Yes, enemies also respawn in Sons of the Forest, and like items, this is often triggered by closing and reloading the game, which creates a kind of default state. It can also occur on leaving and reentering certain areas like caves, though this is a little more unreliable. It also seems to be the case that enemies don't spawn within a certain distance of players, so bases shouldn't repopulate if you reopen the game while you're standing in the middle of one.
However, this all applies to "fixed" enemies, so to speak. The game also seems to have randomly-occurring enemies who spawn in at night, as this doesn't require the game to be closed and opened to bring them back - they just appear in spaces somewhat near to the player after sundown. Of course, making use of the Sons of the Forest sleep mechanics and snoozing through the night might be a better alternative.
Do companions respawn in Sons of the Forest?
No - unlike enemies and items, your companion allies like Virginia and Kelvin do not respawn if they're killed, working under a permadeath principle. If either Kelvin or Virginia die, they're gone for good within that game, and won't come back for any reason. Because of this, you'll want to be sure to keep your Sons of the Forest companions as safe as possible, protecting them from harm and, in Virginia's case, making sure she has the resources to protect herself.
Player spawn locations and setting your spawn point
When a player dies in Sons of the Forest, they either respawn at a cannibal camp, which they have to fight their way out of, or simply die - which forces them to reload a save. For that reason, setting your spawn point isn't really a feature within the game, because you never actually "respawn" - you're either moved somewhere else in the process of being captured, or are just forced to rewind to the last save and try again.
