Question:
What were the names of Jesus’ brothers?

Answer:

Matthew 13:55, 56 tells us that Jesus had four brothers (James, Joses, Simon, Judas).  He also had some sisters, but we are not told how many.  While Jesus’ brothers did not believe on Him while He was on the earth (John 7:5), it seems that at least some of them believed on Him after His death and resurrection.  The books of James and Jude were probably written by brothers of Jesus.