That's a sharp observation. If you're referring to a movie starring Susan Sarandon and Julia Roberts, the most famous (and really, the only major) answer is "Stepmom" (1998) .
Here is why that film is such an "interesting" case study in casting and Hollywood dynamics: susan sarandon julia roberts movie
Stepmom is a perfectly fine, tear-jerking holiday movie, but its legacy is as a symbol of how Hollywood valued youth over talent when it came to the paycheck. That is likely what makes it an "interesting post." That's a sharp observation