I think it is marvellous that you have such a wonderful relationship with your adult children! My daughter is in her early 30's, and I love her so much, but, despite my best efforts, we have a very challenging relationship. She has mental health issues. So do I because I frequently suffer from depression, but hers run a bit deeper than that, which I feel okay sharing because she is very candid about her mental health in public and on social media. She was officially diagnosed with bipolar II, but she disputes the diagnosis and refuses medication. She gets very angry and defensive if I say, really, anything. I find myself walking on eggshells around her.
And then, even though I love her so much, it is very hard to spend time around her, which is sad because our time here is limited, and I would like to spend it with my loved ones.
So, I am always very happy when I hear about people who get along well with their adult children because I think that is how it should be, and it sort of gives me hope. You never know.