1. Work.
2. Boys.
3. Politics.
4. Religion.
5. Boys.
Work was implemented by mom back when we all lived together, so now it's kind of a moot point since she's on the west coast - but hearing about so and so dude in such and such armed robbery gets kind of annoying after a while even for a future cop, so dad tries to keep a lid on it. Politics are just a no in any conversation - we all have our views, but I really don't like arguing enough to want to talk about it with you over dinner, okay. Religion isn't much of a problem since we're ... not the most religious family, even if we're technically Protestant (it comes with the territory!), so the only problems with that are when there are ... particularly pushy guests! Which doesn't happen often. Most people... don't try to get pushy with dad.
I still live on-campus at school, so this is all during visiting and stuff - I have a room mate, but we're never around at the same times so it doesn't matter when it comes to her (see: we always argue anyway).
Sooo, that leaves us with boys. Which are listed twice for a reason! I am the first baby and only daughter, which really sets me up for horrors in that department, in my humble opinion. I realized this quickly when he offered to beat someone up when I was around six because he pulled my hair and I'm pretty sure he was serious, what is my life. Aaanyway, I basically had to make it a forbidden topic because every time that it comes up, either we argue until I leave or something horrible happens.
The last time boys came up in dinner conversation was almost two years ago! Bonus: we were sitting in a hospital, awww. It went a little like this:
"Sooo, dad, you never answered me."
"Lucy McClane."
"I'm just asking! It could be worse, you know. So much worse."
"I fear for my heart if you enlighten me, baby."
"Well I mean, I'm going back to school in a couple of weeks..."
"I'll beat him to death, too."
"So you're saying I should choose the alternative. Eat your dinner before the nurses bitch again."
"I am not saying that and let them bitch, it's not like they can do anything."
"But you like him!"
"Enough to not want to have to kill him."
"Daaaaaaaaaaaaaaaaad."
"Luuuuuuuuuuucy."
I think you get the general drift by this point.
Note: There may or may not have been more actual swearing, I'm not telling.