I remember reading an interview with Rainier at the time of Ernst and Caroline's marriage, LIFE magazine maybe or some other respected outlet. Rainier talked about himself and Grace, and Monaco, and lots of different things, and when he was asked about Caroline's new marriage, he said Ernst's personality was very endearing, with a great sense of humor, and he hoped that they would have great joy in the marriage (those are quotes, I remember things he said I the interview distinctly, because it was nice to hear Rainier so relaxed).