I Found A GOOF/TRIVIA!
Ahem, after thinking about each actresses heights, I searched around IMDB and found them out.
Bette Middler - 5'1"
Stockard Channing - 5'3"
Goldie Hawn - 5'6"
Diane Keaton - 5'7"
The goof is, that at the beginning of the movie when the four take a picture of themselves in College, Channing's actress is the tallest, and Middler's actress is much taller then she should be.
There's nothing much wrong with Hawn and Keaton actresses height though at the beginning.
"Sign it 'Dana Fairbanks - Professional Lesbian'."