No. Jesus is the only son of Mary in the physical sense. [500, 510]
Even in the early Church, Mary’s perpetual virginity was assumed, which rules out the possibility of Jeus having brothers and sisters from the same mother. In Aramaic, Jesus’ mother tongue, there is only one word for sibling and cousins. When the Gospels speak about the “brothers and sisters” of Jesus (for instance, in Mk 3:31-35), they are referring to Jesus close relatives.
