Vivekananda said to him, "What are you doing, what are you doing?" Brahmananda replied in Bengali, "You are my elder brother, so you are like my father. That is why I am bowing to you."
Then Vivekananda touched Brahmananda's feet and said, "The son of the Guru is like the Guru himself."
So both of them were bowing to each other in front of thousands of people.From:Sri Chinmoy,Transfiguration and other stories, Agni Press, 2007
Sourced from https://srichinmoylibrary.com/trn