When did Pete begin to act kindly toward Sucker?

When Pete met Maybelle Watts, he was so happy that he didn't mind Sucker's admiration anymore.

"He used to look timid and sort of like he was afraid of a whack to the head. That expression was gone. His face, with those wide-open eyes and his ears sticking out and his mouth never quite shut, had the look of a person who is surprised and expecting something well."

Sucker became a bright enthusiastic child who loved being around Pete. He was so happy that he did not want anything to change.