or was The Queen Mother, just a title?
i know she will not abdicate, the question was hypothectical
Good question. When Queen Juliana of the Netherlands abdicated in favor of her daughter, she returned to her former title of "princess". Queen Mother might be appropriate, since she’d be the mother of the monarch. (The sex of the monarch wouldn’t have to make any difference, so "King Mother" isn’t in the running, I don’t think.)
Elizabeth, the Queen Mother used that title only to differentiate herself from her daughter who had the same first name. That problem wouldn’t arise in the case of Elizabeth II and her son.
However, I think the Queen is about as likely to abdicate as I am to become Queen.