Santa!

What do you tell your kids about santa? I know as a child (and raised in a very abusive family) i was taught santa doesnt bring presents to bad kids, my parents took it a little too far by buying my sister thousands in gifts and i got little to none because "santa says im a bad child" and then on the flip flop i would go to my biological moms house, and she had very little money often never had christmas presents and because of this never acknowledged christmas at all, i felt like i was being punished again. My toddler is three and i have refrained from using the terms "santa wont come if your naughty" but my husband doesnt agree.

What do you tell your kids about christmas and santa, and im also very interested in learning about holiday traditions (either past or present)