There are many disciples of Jesus in the Bible, but there are twelve that are particularly the disciples, or simply, the twelve. Some of these are related to each other. In the small town region of Galilee where Jesus lived that would not be surprising.
What follows is a summary of the disciples and relatives of Jesus, given that we don’t have as much detail about them as we would like. First, the twelve disciples, which are listed four times in the New Testament (Mt 10:1–4, Mk 3:13–19, Lk 6:12–16, and Acts 1:13):
Simon Peter and Andrew, brothers who worked with Zebedee’s family fishing business. Jesus gave Simon the nickname Peter.
James and John, sons of Zebedee and Salome, whom Jesus nicknamed Boanerges, “sons of thunder”.
Philip, from Bethsaida.
Nathanael Bartholomew (son of Tolmai).
Thomas, also called Didymus (the Greek form of Thomas).
Levi Matthew and James, sons of Alphaeus. Levi was apparently his given name and Matthew a nickname, meaning gift of God. James is sometimes called “James the Less.”
Jude Thaddaeus (or Lebbaeus), son or brother of James. Also called Judas or Joses (Joseph).
Simon the Zealot, also called the Canaanite/Cananaean.
Judas Iscariot, son of Simon Iscariot.
Next, the relatives of Jesus:
His birth mother was the Virgin Mary, and his legal father was Joseph. Mary had a sister or sister-in-law, Mary, the wife of Clopas (Jn 19:25).
John the Baptist was a relative of Jesus since Elisabeth, wife of Zechariah, was a relative of his mother (Lk 1:36).
Sisters (Mt 13:56; Mk 6:3), either half-sisters, step-sisters, or cousins.
Brothers (either half-brothers, step-brothers, or cousins): James, Joseph/Joses, Judas, and Simon. (Mt 13:55; Mk 6:3) James is commonly considered the author of the epistle of James, and Judas the author of the epistle of Jude. James is also called James the Just.