Andi,
It is just such a natural time for you all to be together, I mean, it would be odd at say 8 o'clock to say, okay, let's all sit down and have a chat. When you have kids I highly recommend it, and I agree, it needs to be peaceful, no fighting, etc., just a time to talk. My parents were always very adament about it, that for however long it took us to eat we were going to talk together as a family, probably the only thing that allowed us to work through my rebelling against the borg yet remain on speaking terms.