Question about bar mitzvah

There is nothing definitive about whether a step-father may hold a bar mitzvah for his step-son in G-d’s Torah. Therefore, holding to the concept/logic of kalv’komer (from the lesser to the greater), I submit to you that since this step-father has taken on the young man as his own son, it is permissible. Yahshua often taught using this logic and it is consistent with the concepts of the commands; the spirit of the law, especially when there is no Biblical prohibition (letter of the law). May HaShem bless the family and the event.
Brachas,
Rabbi Tamah