Hello there!
I recently started playing The Sims 2 again and I'm back to my madness of creating Anime characters, but that's not the point

So, I created this household where I played for a while, but then, I created another household that I attached to the first one. (basically all of them living together, 4 people in total)
The first two are brothers, the other two are brothers as well, but they're not all 4 brothers, if you get what I mean.

Thing is, I should have made all of them brothers from the beginning, since that was my intention, but I was too lazy to take care of 4 Sims at one time, so I made them in "batches".
Now, my question is if there's any mod or cheat or anything that I could make all of them brothers within the house? As I can't go back to CAS with them like in Sims 3 or 4.
E.g.: a and b = brothers ; x and y = brothers, but strangers with a and b
What I would want to make is a, b, x and y to be brothers / siblings. Not through marriage or engagement etc.
Is anything like this possible?

I also have a side question. Once I create a Sim in CAS, how can I put that Sim as a pre-made Sim in that Bin thing?
Or at least, once I put them in a house, how do I save them as pre-set Sims after, so I find them in CAS in case I want to use the same faces etc.?
I knew it was possible once, I've done it before, I just forgot how I used to do it back then XD

I hope it makes sense ^^
Thank you in advance!

Yes you can. There are two ways that I know of that will let you do it. First way is to edit their relationship in SimPE, and the second and probably more easier way is to do it with TJ's Sim Blender. There is an option on there that says Family and in it you can tell it to set as sibling.

Just in case ya don't have either ... here are the links:
Here's the link for the Blender http://www.simbology.com/smf/index.php?topic=20.0
And for SimPE http://sims.ambertation.de/en/

For both these jobs, you'll need an editing tool. Many of them will help with the relationships, but to clone a CAS sim you'll need SimPE, which allows you to do everything the other editing tools (SimBlender, SimManipulator, etc.) do plus more, so even if you prefer to work in-game it's a good idea to download SimPE for when you need it. Make sure you get the version suited to your game configuration, which I see you don't specify in your profile.

The basic SimPE download site is here: http://sims.ambertation.de/en/download/
You'll find that this site has not been maintained for awhile, but if you don't panic and proceed methodically you should be able to find what you're looking for. If you'll post which EPs and SPs you have, or add them to your profile, it will be easier for people to help you figure out which version you need and how to get it to do what you want. If you have the UC, I think you'll want the most recent version, but I think I've heard of some hoops that have to be jumped through so I'll let someone familiar with the UC help you with that.

You can, however, use tools that are already on your machine to create sims for the CAS sim bin (just not to clone CAS sims to put there). Bodyshop is also necessary for the last step in cloning a sim in SimPE, so you may as well go ahead and install it. In your EAGames/Sims 2 Program files (NOT the datafiles in My Documents, but the game installation files) there's a version of a program called Bodyshop for each EP you have installed. Open the folder for the most recent EP you have installed and you'll find a folder called CSBin, inside of which is a program called bodyshop.exe. Click it to install that program. It may (okay, probably will) take an age to load, but when it finally does, you'll be able to create new sims. Many people like it even better than CAS, because it has more tools to create more subtle facial sculpts than you can get in CAS. This is also where people recolor clothing. Sims you create in bodyshop are saved to a Saved Sims folder, which is then accessed by the CAS simbin for the age group you save the sim as. (Bear in mind that YA sims will only appear in the CAS for your University subhoods.)

When you have finished using bodyshop, you'll need to go into your Sims2 data folder and delete your cache files and two new files that Bodyshop will have created - Content Registry and Cigen - before trying to open your game again, or the game will never load.

Thank you both, first off! This is going to help a lot.
@CaliBrat I'll try the SimBlender first, as SimPE still confuses me.

Also, @Peni Griffin, I have the complete The Sims 2 game (with Double Deluxe as "base").
I know bodyshop takes a while to open, I remember that from my older PC, but on this one, it takes a few seconds now that I think of it. I used it before to create clothes, well recolor them.
Now, it will take me a while to get used to using SimPE tbh. I tried it before, but it confused me to hell, so since then, nope, haven't been using it much XD (I don't even remember what I needed it for)

SimPE looks intimidating at first sight, but that's because there's so much you can do and check with it. If you focus only on what you're trying to do right now, it's simple enough.
Cloning is done through a plug-in called Sim Surgery.

These tutorials for cloning sims are very old but the basics haven't changed, so which ever one confuses you least can get you started: http://modthesims.info/t/37817
http://hullabaloo.sunsims.com/forum...opic.php?t=7770
http://pixel-trade.livejournal.com/16091.html

Although the clone you make in SimPE will appear in the sim bin, it's Best Practice to run it through Bodyshop before using it. Why? Well, if you compare the file you cloned in SimPE with the bodyshop clone file (which will be automatically named random gobbledygook; but if you check right after you clone it you'll know it because it will be the most recent. Feel free to change the name to something meaningful), you'll see that the SimPE clone file is much bigger than the Bodyshop clone file. Why is this? The SimPE clone contains more information than the Bodyshop clone. What information? Well...no one's entirely sure. If you clone a sim in SimPE and look at it in CAS, it will retain all the outfits assigned to it, whereas a Bodyshop clone only remembers the outfit that's visible on the clone's thumbnail, which seems harmless enough, but nobody's certain that's all that's retained. The difference in size is often much larger than you'd think, if that were the only infor retained. Of course Bodyshop may compress data differently...but no one's sure. So the fear is that information in the file is of the sort that causes hood corruption, and a Bodyshop clone is certified free of all that jazz.

So skip the Bodyshop step at your own risk, and never share a sim clone that hasn't been run through Bodyshop.

This tutorial will help you change relationship in SimPE. Most editing tools don't change the family trees, and SimPE allows you to do it (It will not happen automatically!), so I personally prefer it.
http://hullabaloo.sunsims.com/forum...opic.php?t=7085

Thank you! maybe this is going to erase the confusion I have about SimPE. It sounds easy enough, to be honest. Thanks again