Random lagging when moving camera

@ManeEvent4U2  I didn't realize you and your sister play on the same computer, rather than the same type of computer.  (Is this in fact what you're saying?)  Do you each have your own game folder?  (This would necessarily be true if you each have your own user account.)  Do you tend to play in the same worlds as your sister?

Even if I read your last post wrong and you're not sharing a computer, you could always try a clean folder.  Pull your existing game folder out of Documents and onto your desktop, and a clean folder will spawn the next time you launch the game.  Try playing a brand-new save in a well-made EA world like Sunset Valley or Twinbrook.  If your graphics look better, the problem is either in your old game folder or in the worlds you're choosing.  (Isla Paradiso is notorious for being so poorly made as to be almost unplayable even on the best systems; Bridgeport is better but will stress computers with weaker specs.)

If the clean folder does run better than the old one, you can move your existing saves and other content into it from your old folder, a few files at a time.  Be sure to check the game after you add each batch of files—if the game starts having trouble again, you'll know that one of the files you just moved was the problem.

I understand that you already tried removing custom content from your game, but you would also have needed to clear your cache files afterwards to see the full benefit.  (The clean folder will take care of this.)  Going forward, you'll need to avoid "high-poly count" items (especially hairs), as they'll be too much for your graphics card to handle.  Many creators offer both high- and low-poly versions of their creations; their descriptions should tell you what you're getting.  And you can always test out new cc in a clean folder before adding it to your existing game.