I would love to know the popular opinion on this topic.

I started going to my hairstylist when she worked at a regular salon. I always gave her 20% tip. A few years ago she opened her own salon but I continued giving her 20% tip because I felt weird about not giving her tip all of a sudden (even though I know you don't have to tip if she is the owner) plus she's amazing. This brings my total from $200 to $240 so it's a significant amount of money.

In the past she worked without an assistant but recently she hired an assistant who does the shampooing. That's pretty much all the client interaction the assistant has (I think she put the color block around my hairline as well).

Do I have to now also tip the assistant? At previous salons I'd leave a few dollars for the assistant and 20% for the stylist but it was never the owner. Can I expert my stylist to tip out her assistant?