Answer:
Many things have changed since his mother remarried. One of the major changes are his appearance and his social circle.
Explanation:
He is the son of Undine Spraggs. She is a midwife who divorced her husband and went to marry a wealthy man named Ralph Marvell, just for the sake of luxurious. She used to live in a small town but persuaded her family to move to New York.
She even leaves Ralph with Paul to go on a trip to Europe. She rarely gives her son the attention he needs.
Later on in the story, she even leaves Ralph to marry another rich man. She knows how to make her way in the society and has a never-ending greed for money.