Please summarize the events surrounding Dev's Udyapan ceremony and Sai Baba's mysterious attendance.

In the account from Chapter 40, a devotee named Dev held an Udyapan ceremony and lovingly invited Sai Baba, who promised to attend. However, Dev did not see Baba arrive in his familiar form. Feeling disappointed and deceived, Dev wrote a complaint letter to his friend Jog. In reality, Baba had attended in the guise of a Sanyasi, first appearing alone and then returning for the meal with two companions. When Jog relayed Dev's complaint, Baba explained how he had kept his word. Upon learning the truth from Jog, Dev was overcome with shame and remorse for his lack of perception and for blaming Sai in vain.