As former high school teacher and coach, there's something that always strikes me when school starts in the fall and we stumble upon National Suicide Prevention Week in September: the reminder to teens that no one should keep the secret of the suicidal friend.
Sometimes teens (and kids, too) share with each other what they're afraid to tell their parents or any other adult. Sometimes they think adults aren't aware because everyone is busy and more caught up with what's going on their phone rather than around them.
Instead, teens might share in passing to friends that they are thinking of killing themselves. Whether they are or aren't isn't the question here, instead it's about making sure that secret isn't kept by the person who has become a keeper of it.
Teens should know to always reach out to an adult they respect and trust, that if they are suciidal it's okay to get help. And if a friend has confided in them, they should share the secret rather than holding it inside and worrying what might happen to the friend.
They are surrounded by adults, maybe not their parents who are dropping them off at activities after school and picking them up and taking them home in time for dinner, homework, and bed, but also coaches and other mentors. In there somewhere is someone they respect and know will help.
Bottom line, teens don't always have to share with their parents what friends have told them. It's okay to reach outside that circle to another adult as long as the secret isn't kept. After all, the friend might be reaching out to the teen because he or she believes the cry for help will be heard by that person.