RCC believes that the early church considered Mary a virgin forever. It's in their (early church) writings and prayers. Ergo, any "brother" is either fraternal or by some other Mariam. Does not necessarily rule out other children of Joseph, however. He does not get much mention after the nativity.
Another hoax, just like the Piltdown Man! How many more hoaxes must we endure before evolution is finally buried and forgotten by rational people?
(what's that you say? its' a Christian hoax? OH! in that case, nevermind!)