Is there a resource on the relationships between Sims 3 worlds? I'm looking for answers for the following questions:

1. Is there a way to play households in sub-worlds?
2. If so, is there a way of adding home worlds as sub-worlds in a home world?
3. If not, how does moving to different worlds work?
4. (sub question a) Does having a Sim move to a different world cut all relationship ties between the Sims of the old world? (What about the family tree)
5. (sub question b) Is there a way to move a Sim/Household to an already existing save game or would the only way be to package them and move them?

I am asking this because I am currently playing a TS2-style aging (only currently played household ages) game of Sunset Valley and Riverview. As most people know, the two neighborhoods are linked (particularly as it relates to the Broke family), but I'm confused as to how exactly I can connect the two neighborhoods. Ideally I would like for them to be as connected as possible.

Another problem I am having is that in my timeline of events, Michael Bachelor moves out of town (Barnacle Bay) where he meets Dina Caliente and they elope, he dies, with Dina and Nina then moving to Sunset Valley (Pleasantview). I'd like, then, for all the family ties and such to stay intact for when Dina moves back to town. I am worried that if Michael moves out of town, he will be removed from the Bachelor family tree (or almost worse.. he is still there but forever in the state that he was when he left).

In the end, my goal is to progress the timeline along to the start of TS2 with all the TS2 characters as well as all the new TS3 characters and hopefully, the TS1 characters sprinkled in.

1-4. There is no concept of a sub-world in TS3. The playing of multiple worlds within the same game though, connected and with relationships, family trees, and the ability to move and travel between them preserved, can be accomplished by using NRaas Traveler (Overwatch and ErrorTrap highly recommended to accompany it). The game engine can only simulate and progress one world at a time though, so the others not in active play go into states of suspended animation until a sim travels there again. Whether sims age or not in worlds other than the active one is up to the player on a per-world basis as per settings on City Hall > Traveler.

http://nraas.wikispaces.com/Traveler+FAQ (see especially the Switching Homeworlds section towards the end)

5. You cannot move sims or households from one game save to another without their losing their history and relationships with those whom they have left behind by using such methods as the household bin or NRaas Porter. But with NRaas Traveler, you can place a copy of the nhd file of the world from one saved game into the saved game folder of another and then travel/move sims between the two (or more) already played and progressed worlds. The goal here would be to have one blended ongoing saved game, not several separate ones going forward.

I currently have 16 Traveler connected worlds in my one ongoing, long-running game. "My" sims live in 5 of them which I rotate active play through, the others are custom vacation destinations, the three WA worlds, Uni, Oasis, and a couple of places where "my" sims used to live but still have distant relatives back there. This can get a little confusing, but I allow aging in the non-active worlds that I only visit occasionally only when I am playing the "main" household in my "main" world so that things stay on a more or less even keel. For the worlds I rotate through and play properly, I disallow aging when they are not active so they can age normally when I do play and get them caught up with each other.

This is all extremely helpful, thank you so much! Exactly what I hoped for. Funny thing is - I actually already had Traveller! I had downloaded it years ago and forgotten why I had.

Let me double check what you are saying. If I were to have a saved game of let's say appaloosa plains and then a separate saved game of sunset valley there is a way with this traveler mod to combine the two into one save file? That would be the bee's knees. I read somewhere that wasn't possible so that's why I'm wanting to be sure.

Hmm...I'm not sure we're talking about the same things. I understand that you can travel between worlds in the same save and that it treats the other worlds as if they are vacation worlds. From what I gather though, when you travel or move to another world, it loads the world up as it originally came. If you had altered the world in any way, in a completely different save file, then those things are not going to display because it's choosing the file that came with the game and not your different save file. What I'm asking is, if you are in one world, appaloosa plains and then play and save that as one save and then start an entirely new game let's say in sunset valley, play and then save that file can you then combine the two entirely different save files so that if appaloosa plains is your main neighborhood and then you want to visit sunset valley you will be taken to the sunset valley you have altered and not a fresh one? Sorry if that's what you were saying already but I wasn't understanding.