Hey @
digibud - yes indeed your sister might find The Unlikely Cyclist (1673 Irvine Ave, Costa Mesa) to be just what is needed to help her if she truly wants to get involved in cycling more and to feel more confident no matter where she rides.
Lisa (@vntgdrms) is the owner. She is a fabulous source of info and encouragement. She (and I) love to mentor new riders and watch them grow. Her shop has a slogan of "empowering women" and she means it.
Have your sister stop by and just check it out with no pressure. Lisa is friendly and very welcoming.