Although we can only speculate, one reason may be because such appearances better fit the message he is giving (e.g., humility, childlike trust) or the messenger who is holding him (e.g., the Blessed Mother, St. Joseph, St. Anthony of Padua). Another reason may be to remind us that Jesus’ childhood was not merely something he had to “get through” in order to become a man and complete his mission. His childhood was part of his mission, as was his entire life. By his childhood he sanctified childhood, just as he sanctified all stages of human existence by living them.