What to do if you missed a stuff pack.

I have installed all the sims 4 from games4theworld however I accidentally missed my first pets stuff.




Gatekeeper Edit: moved to the right section.

- The_gh0stm4n

1. Either re-install My first pet stuff and all DLC's thereafter.
2. Or use @Anadius alternative downloads

Do I just have to reinstall from MFPS?

and is there a way to prevent me from losing my saved games?

Any updates/deletions will NOT affect your saved games, mods, tray etc. 
They are safely stored in Username\Documents\Electronic Arts\The Sims 4 and that folder will not be altered by new installations.