Better safe than sorry?

*emptying pencil box*

Dad: What're you doing?
Me: Taking out my pen knife. Can't carry sharp objects. Invite card says it's a security threat, apparently.
Dad: *mock incredulity* So you gotta file your pointed teeth too, eh?
*Mum chokes on her drink in silent laughter*
Me: *exasperation* You can't hurt people with pointy teeth lar!
Dad: You could bite them, ahahahaha. Precautions, you know.