It would be very effective in creating the character of grandad. I think the author choose to have him speak with profane language because some people thought it was wrong to move to the new country and settle there so when the author made it so grandad using profane language it showed that he did not care what people thought of him. It was very effective in creating the character as he stood out he was not like the rest where they didn’t use the profane language and were lumped together.