She did manage to get a supporting role in the movie Falling Down and predominate sitcom roles in the '90s (Cybill and For Your Love) but she never became an A-lister like her sister. Dedee (https://www.horrorsociety.com/2017/01/24/now-dedee-pfeiffer/) based on some of the comments that I've read elsewhere, could've been Cameron Diaz (https://www.filmboards.com/board/p/2550348/) before we ever heard of Cameron Diaz.

Was it simply because Dedee at the end of the day, never had what it took to be an actress? Was the main reason that she was cast because of nepotism and her sister? In effect, you can say that there is a lot of nepotism in the entertainment industry, and the people who are really talented don't have a chance to succeed.