My eyesight is not what it used to be but I can’t seem to find the part in Rob’s sandbox write-ups where it instructs the GM to kill a PC’a lost brother that they declared they are looking for.
I apologize if it been mentioned before but in sandbox campaign context is everything. I went back a few pages reading the debate on the PC's lost brother and the result I couldn't weigh in because I don't see the context. I don't know what the PC circumstances, I don't know the Brother's circumstances, nor do I know anything about the setting. Until the specifics of circumstances are outlined one can't judge whether situation was a fair ruling by the referee or not.
The general principle I operate by (and stated in my blog Bat in the Attic). Is that I set the table so to speak in terms of the setting. While I may not have everything described my assumption and what I relay to my players is that the setting has a life of it own. It existed prior the campaign and it will continue to exist after the campaign. The PCs in essence are pebbles dropped into the pond of the setting and their ripples interact with other ripples that I defined.
The campaign starts with the initial drop with the PCs having some idea of their place within the setting. After that first session and every session afterwards I will then see what the PCs do or not do and adjust the circumstances of NPCs accordingly. I rinse and repeat this throughout the life of the campaign. If I run another campaign in the same setting, I tend to stick to the same setting for the same genre, then the results of the campaign becomes part of the background of the next.
As for the situation of the lost brother, it speaks to the part where I adjust the circumstances of the NPCs as a result of what the PC do or not do.
Typically for something specific like that I look to the players provide the information that sets up much of the lost brother's circumstances. Based on that information, I will look at several situation that are plausible and interesting. If several have equal weight I will randomly choose one. Judicious use of random table it is good way to force yourself out of one's bias occasionally.
I strongly people trying to run sandbox campaign to assemble a decent set of the random tables that reflect the range of stuff the setting has.
Note I said plausible. The new circumstances needs to follow out the consequences of the reaction to the old circumstances. While there is a probable outcomes most times there is a range of possible outcome and this is where the creativity of the sandbox referee shines. You don't have to always go for the probable choice is the other possible choices are plausible. (mmm a lot of Ps there). So I recommend going for the option that is interesting to the campaign but still make senses in light of the circumstances. And occasionally do a random outcome roll to keep yourself honest.
But not all circumstances have multiple outcomes. Sometime the probable outcome is so overwhelming that it is the only choice. In the context of this discussion that means the lost brother dies despite it being a major part of the PC's drive and motivation.
Having said that let's keep several things in mind.
One common issue I see with people running campaign is simplistic outcome. That there only possible and probable outcome to the PCs choices. Having lived a few decades now, and with the experience playing MMORPGs with multi-players and more important playing and running LARP events. It is rare that situations are that simplistic.
Of course without experience it hard to think of all the possibilities which why assembling a good set of random table is a great help to the novice. Not only they generated varied result, they express in a compact form the range of possible results.
The reason situations are into simplistic is something I call situational awareness. Usually it used in the context of combat but here I including social situations. People are aware of their surrounding and who there and sometimes who not there. A sandbox referee needs to learn how to incorporate this situational awareness into their descriptions of locales and NPCs. As it usually result in multiple and unexpected paths out of the situation. What I do is visualize the circumstances as if I was standing there as a witness. Then I pare out the details to those that are relevant and manageable.
Circling back to the lost brother, which is why in order to weigh in on the lost brother I need to understand the specific circumstances. I will also add that without the possibility of failure, sandbox campaign lose a lot.
Last people forget that as a referee that they need to a coach especially for a detailed or new setting they created. Players are not going to get all the detail right off. So you need to don the coach hat and teach them what their character would know about the setting.
Hope this helps with the discussion.