The 38-year-old football star planned to tie the knot with Priscilla Coelho and Beatriz Souza, both 30, in August, according to recent reports.
But the former Barcelona player’s sister will not be there, Dias said, because she does not agree with his lifestyle.
Ronaldinho, who is said to have given both women engagement rings in January, apparently already lives with them.
Ronaldinho is said to have started dating Ms Beatriz in 2016, several years after he met Ms Priscilla. Even though Bigamy is punishable by up to six years in prison in Brazil.