Mark 1:19

And going a little further, he saw James the son of Zebedee, and John his brother, who also were in the boat mending the nets. And straightway he called them: and they left their father in the boat with the hired servants, and went after him.

These brothers also were among those whose first meeting with Jesus was recorded by John; and it is true of them, as of Peter and Andrew, that this was a formal call to the apostleship, significantly afterward. Their response, like that of the others, was prompt and obedient.