I'm 42 and grew up in southern California. My parents got married, bought a house, then had us 3 girls - all in that order.  They are now retired and still married after 50 years of marriage.
 
A few rules I remember from childhood:
 
1. No phone calls at dinner time. At 5:30pm every single night, all 5 of us would sit at the dinner table and eat and talk about whatever. We said please and thank you when asking food to be passed and we asked to be excused from the table when done. We were taught RESPECT for our parents and RESPECT for family time. No phone calls or technology of any kind were permitted during family time and I still look back and treasure that today.
 
2. My mom was adamant that absolutely no favoritism would ever be shown and so all 3 of us were treated equally and fairly. Bedtime was 9:00pm until we were 16 and then midnight after that, for all 3 of us girls. All 3 of us were even given the exact same amount of money to go toward our weddings, despite our differences in income, lifestyle, and when our weddings occurred. I am sooo grateful for this now, especially when I hear girlfriends talk about the pain of enduring favoritism in their family as a child.
 
3. On Saturday and Sunday mornings, NO ONE was allowed to knock on their bedroom door until 10:00am. They always locked their bedroom door and we were never to knock or disturb them unless "the house is on fire or someone is dying." We could read, play, and pretty much do whatever we wanted as long as we remained semi-quiet and didn't disturb them. I didn't realize it then, but this was probably one of the few chances they got each week to just be with each other, relax, and enjoy one another's company...if you know what I mean. I have no doubt this is one of the many reasons they are still together today.
 
Those are just a few, but those stand out to me the most.
 
Cheryl