Know where your children are, what they are doing, and who they are with. Get to know their friends and their friends' families. Toddler or teen, all children need direction. It takes more than just parents to raise a child. Reach out, find supports, make friends.
Nobody is perfect.
Our children need to know we still love them and believe in them even when they make mistakes. My father had faith in me and loved me. Maybe you don't exactly learn from that, but it allows you to take on the world. I grew up knowing I was accepted and loved, and that made an incredible difference. There are many kinds of families.