How many children did Scarlett O'Hara have?

She had one in the movie, but three in the book.

In the book, she had one child with each of her husbands.

She had a boy, Wade Hampton Hamilton with her first husband, Charles.

She had a girl, Ella Lorena Kennedy, with her second husband, Frank.

She had a girl, Eugenia Victoria Butler, nicknamed Bonnie Blue, with her last husband, Rhett.

In the film, she only had Bonnie.

She also became pregnant after Bonnie's birth with a second child for Rhett, but fell down the stairs and lost the child.

In the authorised sequel, Scarlett, by Alexandra Ripley, she had another child by Rhett, Katie Colum O'Hara, or Cat.