Right after the marriage, I saw Diana (not in person, of course) as a deer (or doe) in the headlights. She never looked secure or comfortable as Kate does.
Then the interview with the black smudged eye makeup to make her look like a waif who had been crushed under the pressure of being a part of the Royal Family.
Then that black tight "hooker style" dress when she emerged from her cocoon to show Charles just what he had lost.
Then the all too revealing shots of her and Dodie on the yacht and we know that her sons were often with her. Was is a good mother who flaunted her lovers in front of her sons?
I do think that a lot of the "bad behavior" that we saw in Harry came from his mother's bad examples. He was so young when she died.
And, yes, Charles also engaged in "bad behavior", but for different reasons. He wasn't out to prove to anything to the world because he had already begun the Prince's Trust. He had his place in history set for him and some of the mistakes his parents made in not allowing him to marry the woman that he loved caused the problems that he and Diana inherited.
But good or bad, both princes love their mother and cherish her memory. Otherwise William wouldn't have given Kate that cursed sapphire ring. I don't think I could have accepted and worn that horrible symbol of that failed marriage. Kate has spunk and panache. Also, she must love William a great deal.