Celebrity Relationships?

To help in further increasing her fame this way, make sure your sim and her celebrity friend is out in public for other sims to see the interactions. But to answer your question, I really don't know how much.

Yes, it certainly will. Be sure to choose the Networking fame perk if you haven't already to get the full benefits of befriending other higher ranking celebs. You'll see a green fame+ added to interactions that will help you gain fame faster.

Yeah, seconding what's said here. Being out in public is a must, and having the networking perk helps a lot. But my sim started dating a 4 star celebrity, and gained quite a bit of fame just from making out in public lol.

Can't remember what it's called, but there is a fame debuff where the sim always wants to rub elbows with famous sims. Problem is, it's MORE-famous sims. So, as your sim gets more and more famous, it gets harder and harder to keep from getting the debuff.