This happens, and there are plenty of in-game tools to deal with it. Throw the person in question on your ignore list if you think it warrants it and move on is my advice. I personally would only do so if they became a pest about it. This is a game and many kins are social, for fun, and not professional baby-sitting. If this happened to me, I wouldn't think any less of the KIN that the player happened to be a part of. I don't think the kin I am in has any more formal of a "code of conduct" beyond "Don't be a d*****." And even then, I'm not sure it's official policy, instead of simple common sense.
Parahelion - Burg, Krustii - Champ, Shurmann-Cappy, Tommac-Min, Lazarrus-LM, Thromdir-Hnt, Theodolan-Grd, Kozzmeaux - Bear - Dancing in the Dark kinship.
Wrecks - Warg - The Black Blade