One thing I would tell those who worked for or with me. When on a business trip to never dip you pen into the company ink well. Then ramifications, if any realized, can be disastrous. I expect this thought can be applied to family affairs also.
Secrets? Thats often tricky and I say that in the reverse way from how many may think. One fiancee, mid 20s, wedding booked and all deposits paid (by her, with me due to pick up the balance later). We were openly into sex with and infront of close friends. Two couples. Nothing secret until one day, a work colleague asked me if I was sure about marriage. Long story short, he gave me a lust of 8 guys she'd fucked, often staying overnight with them. I confronted her. She denied it. She was extremely angry that I could say such things. And then I gave her list of their names. And I gave her a list of others who knew what she was doing. That included her parents and uncle as well as cousin. None had told me. So that ended, not because she had sex with others but because of lies and deceit. Next one started as relaxed fun. She was known to be quite friendly and I discovered she was quite adventurous. She liked 3sums of all types and was quite uninhibited. First night we met we were both naked in minutes in a public but largely deserted park. And she stayed naked and masturbated as I drove to my place. At her place, which she shared with two other mid-20s girls, if one of them came back to the house and we were shagging, it was no big deal - she kept going or told me to. It became a thing briefly that any of us could play with anyone from that group. I sometimes arrived to find her and one other of the two girls naked in the living room with toys and so occupied with each other that they didnt hear me arrive. If she had sex with anyone else it was with me there too. No deceit at all. Easy to accept and live with and we're still friends though we don't see each other so much. So no secrets to keep from her. When I described some she arranged something similar but more mind-blowing so we could, together, claim those memories and erase the earlier ones. Now the more recent one who, from when she met a previous one, insisted her name and existence were never mentioned again. The mere fact we'd had sex spiked her jealous streak. The fact that we had several firsts together was criticised so no more history was revealed. On reflection, I find it very interesting that she; the second one of those, the one who many considered a true slut, was much more easy to get along with, to trust and rely upon as well as to push boundaries with. Oh - and she wasn't actually a slut. She liked sex. Offered me everything and ensured I was never in need, if she was able to meet up and we were within 100 miles of each other. But she never did anything secret. We ended for other issues which don't need to be divulged publicly. There's been others of less significance but none shared secrets like this thread is about.
Definitely good advice. Luckily for me, I dipped my pen plenty of times in the company ink without having any issues. Lucky I guess.