"One day Father had an altercation with Petrushka, and the boy was sent away."

I wouldn't be at all surprised if the truth behind this sentence is that the father noticed "the boy" (i.e. the young man) ENJOYED the time he spent with her, and THAT ALONE was why he was "sent away" with absolutely no other reason needed. It's too bad she couldn't give any more details about this "altercation" between "the boy" and her father that she considered a tragedy, and too bad she didn't find out the truth about it later. I wouldn't be at all surprised if this was just the first of many times Petrushka was treated that way after bringing joy to some child's life.