- Express feelings of sadness and/or hopelessness. Don't write off a statement like, "I hate myself" or "I'm never going to be able to (fill in the blank)" as teenage dramatics. It might not be.
- Think and talk about death and suicide. This is a big blinking neon sign, obviously. Don't hope it will go away and/or be afraid to ask the young person about these thoughts. Depression can make suicide seem like a perfectly natural solution, even to adults. That's the kind of thought process that urgently needs to be addressed.

One of the most important signs overall is change. Don't just brush off any change in behavior as a normal part of growing up. Some change is normal, obviously, but when the changes are all negative, that should tell you something.

If you're finding that you're not able to get any helpful answers from your child about what is going on, you might want to enlist the aid of a school counselor, teacher, coach or spiritual adviser. Sometimes teenagers are more comfortable talking about their problems to someone other than their parents.

Even if your child seems to resent your concern, don't be afraid to keep pushing until you're satisfied that things are fine with him or her. Remember, deep down a teenager doesn't really resent your "interference." Even if they're grouchy on the outside, they're secretly happy that you care enough to worry.