When did Johnny first speak English in the book the Light in the Forest?

Johnny first speaks English when his white father, Harry Butler, tells him that they are within sight of the place where he was born, Paxton township.  True Son responds to this information with a look of terror, and utters "in thick, Indian English", the question,

"Place of Pashtank white men?"

Mr. Butler, pleased that True Son has attempted to speak in English, replies,

"That's right, son.  Peshtank or Paxton.  It's the same thing".

True Son is horrified at this news.  He remembers the "Peshtank story" that had spread through his village, a story of violence and deceit perpetrated upon the Indians by white men of Paxton.  The victims were a tribe of Conestogo Indians who had adopted the Christian faith.  "White savages" from Peshtank inexplicably came to their village one day and massacred the people, who put up no resistance.  Those Conestogo who had been away at the time of the attack returned to find their people killed.  They went to the town of Lancaster and asked to stay in the white man's jail, where they believed they would be safe.  Tragically, the "white barbarians" came to the jail, broke in, and murdered them all, and no one in the white population made any attempt to stop them.  It is the Indian custom to adopt individuals taken prisoner, but the Indians have come to understand that the white man apparently shows no such mercy; they "do not want the Indians even to share the common air". 

Harry Butler believes that True Son should be happy to hear that they have arrived at Paxton, the town of his birth, but ironically, the name only reinforces the youth's anger and hatred of the white man.  After expressing his dismay through the utterance of his first English words to his biological father, True Son makes another desperate attempt to escape and return to his Indian home (Chapters 6-7).