30 Especially is this so in the joyful mysteries, which end with the one in which Jesus, after manifesting His wisdom in the temple, came with Mary and Joseph to Nazareth and was subject to them, preparing, as it were, for the other mysteries which are more closely connected with the instruction and the Redemption of mankind. From this all the members may understand that it is their duty to be devotees of the Rosary themselves and to be diligent in propagating deviation to it among others.
Source: Magnae Dei Matris (Vatican.va)