So I was brought up that if you stay with someone for the weekend, or go to a big event that they've paid for, you write a thank you note. My DH's family come to stay but they don't bring anything (I mean just a small something, like chocs or a bottle) or write thank you notes.They are good people, but this rubs me up the wrong way, and I don't feel I can say anything to DH. They are his family - and similarly, he went with my to my brother's big, smart 50th dinner recently - all paid for by my brother. And it was just me who wrote a thank you card, though I got him to sign it. He's a lovely partner and a good man. But I struggle with this as I think it's rude... I think it's just different upbringings (we are from quite different backgrounds) and that doesn't bother me, but I do think thank you notes are important in some cases. WWYD? I guess it's just clearly something he and his family have never been told to do, whereas I had it drilled into me as a child!