Jesus' brothers and sisters. The Gospel of Mark (Mark 6:3) and the Gospel of Matthew (Matthew 13:55-56) mention James, Joseph/Joses, Jude and Simon as brothers of Jesus, the son of Mary. The same verses also mention unnamed sisters of Jesus.
Matthew 12:46 While Jesus was still talking to the crowd, his mother and brothers stood outside, wanting to speak to him.
47 Someone told him, “Your mother and brothers are standing outside, wanting to speak to you.”
48 He replied to him, “Who is my mother, and who are my brothers?”
49 Pointing to his disciples, he said, “Here are my mother and my brothers.
50 For whoever does the will of my Father in heaven is my brother and sister and mother.”
The language here tells me that yes indeed, he did have biological siblings.
John 7:3 "Jesus’ brothers said to him, “Leave Galilee and go to Judea, so that your disciples there may see the works you do."
So we see that not only the disciples are being referred to here too.