Madonna is not to the type of person who would simply walk away from marriage, according to her estranged brother.

Christopher Ciccone said his sister would fight to save her marriage to director Guy Ritchie, which is reported to be on the brink of collapse.

In an interview with ABC, Ciccone also said that he doubted reports linking the pop star to baseball player Alex Rodriguez.

"I believe that she will do what's best for her family and her kids, and I think that she'll do her best to maintain the marriage and keep it going,” he said.

A spokesperson for Madonna has already denied speculation that the singer and Ritchie are set to divorce, as well as claims that Madonna is responsible for the recent breakdown of Rodriguez's marriage.

Ciccone is currently promoting a book about the pop star entitled, Life With My Sister Madonna.