Did Yogananda say what the name of Jesus’s sisters were? 2. Did Yogananda say who the guru of Jesus was?
No, Yogananda did not mention any sisters of Jesus or their names.
Yes, Yogananda wrote and spoke in depth about how Jesus’s Guru was John the Baptist, due to their associations as guru and disciple in a former lifetime as Elisha and Elijah — Yogananda speaks of this matter primarily in his interpretations of the Bible.
Here is a section from Revelations of Christ:
“Paramhansa Yogananda explained that John the Baptist was Elijah in a previous lifetime described in the Old Testament] had been one of the great prophets of olden times by the name of Elijah. Jesus in that previous lifetime had been his disciple, Elisha (on whom Elijah, at death, cast his mantle [all his spiritual power]).
‘And his disciples asked him, saying, Why then say the scribes that Elias must first come?
‘And Jesus answered and said unto them, Elias truly shall come, and restore all things. But I say unto you, That Elias is come already, and they knew him not, but have done unto him whatsoever they listed. Likewise shall also the Son of man suffer of them. Then the disciples understood that he spake unto them of John the Baptist.’ (Matt. 17:10-13)[Even though John the Baptist had been Jesus’s Guru in a past lifetime] Jesus [due to his present state of spiritual advancement] had no need of baptism from John [in this lifetime]; in fact, John said as much. Jesus, however, requested the grace [ritual] of baptism from him in order to show everyone…the fact that this [finding and establishing a close relationship with one’s true Guru]…is the need of every true seeker.”