Watch for the change, not the mood

Quick answer: Don't measure your kid against other teenagers. Measure him against himself six months ago. One shift is usually just growing up. Several shifts at once, especially with a new secret attached, deserve a calm conversation.

The wrong yardstick

Most parents ask, "Is this normal for a 15-year-old?" It's the wrong question, because normal covers a lot of ground. Some teenagers slam doors. Some go quiet. Some live in their rooms.

Ask a different one: Is this normal for her?

A loud kid who goes silent is a change. So is a quiet kid who suddenly turns defiant and secretive. You know your child's baseline better than any checklist does. The federal agencies that work on this, including the Department of Homeland Security's Blue Campaign, list sudden changes in behavior, attire and relationships among the indicators. The key word is sudden.

Mood versus pattern

Ordinary acting out tends to be loud, and it's usually about you. It's aimed at rules, curfews and the dinner table. The kid is pushing against the walls, and you can see it happening.

Exploitation tends to look different. Polaris Project, which analyzes trafficking cases in the U.S., describes a pattern in which someone builds trust first. They offer attention, friendship, a relationship or gifts. Only later does control show up. So the early changes often look like a kid who has found something good and is guarding it.

Watch for these, especially in combination:

• A new person who gets protected. The kid talks about a friend or "boyfriend" constantly, then stops mentioning them. Or you never get a last name, a photo or an address, and questions get a flash of anger.
• Possessions you didn't buy. A phone, clothes, jewelry, cash or gift cards, with a story that shifts when you ask. The Blue Campaign's indicator lists include items and money a young person can't explain.
• A device that became a vault. The phone is face down, the screen gets angled away, new accounts appear, and a second phone or app you've never heard of turns up. Privacy is normal at 15. A sudden wall of it is something else.
• Fear tied to messages. The kid goes pale when the phone buzzes, or checks it constantly and looks sick afterward. Some of the most common online schemes run on fear and a ticking clock.
• Older and unexplained. An older "friend" who has no business being in a child's life. Rides from someone you haven't met. Time away that doesn't add up.
• School and routine falling apart. Missed classes, slipping grades, dropped teams, a friend group that vanished without a fight.
• Exhaustion or changes in how the kid carries himself. Unusual tiredness, being unwell, looking hungry, or a flatness that wasn't there before.

One of these is a Tuesday. Four of them, within a month or two, is a pattern.

Boys get missed

Parents tend to picture a girl. The picture is too narrow.

The FBI and the National Center for Missing & Exploited Children (NCMEC) have both warned about financially motivated sextortion, a scheme where a stranger online pressures a young person and then demands money. The FBI has said most victims of that scheme are boys, typically between 14 and 17. These boys often go quiet, get jumpy about the phone, ask for money, or suddenly can't explain where their cash went.

A boy who's ashamed won't tell you. He'll just get weird. If you're handling the weird as a discipline problem, you may be punishing a kid who's in trouble and afraid of you.

If this one hits close, read what to do in the first hour after a sextortion threat.

The myth that costs time

Most parents are watching for a stranger. Exploitation of children more often involves someone the child knows, or someone they met online who spent weeks becoming a trusted friend. That's why the signs show up inside a relationship the child defends. Why the white van myth leaves kids unprotected covers it in full.

This also explains the hardest part. A child being groomed often doesn't see himself as a victim. He thinks he's being treated well. He may defend the person, lie for them, or get furious at you for asking. That reaction isn't proof of guilt on your kid's part, and it isn't proof of nothing. It's what the pattern does.

What to do when you see a pattern

Start private and calm. A kid who senses a trap shuts down.

1. Pick a quiet moment. In the car works, because nobody has to make eye contact. Don't do it in front of siblings or at the dinner table.
2. Lead with what you've noticed, not what you suspect. "You've seemed worn out for a few weeks and I've been worried about you" works. "Who is he?" doesn't.
3. Say the sentence out loud. "Whatever's going on, you're not in trouble with me." Then mean it.
4. Don't promise to keep a secret. You can promise to stay calm and to help. You can't promise to say nothing if a child is in danger.
5. Don't delete anything. Messages, accounts and usernames can matter later. Screenshot and save, and leave the accounts alone until someone qualified says otherwise.
6. Don't rip away the phone in a rage. Taking devices may be necessary down the road. Doing it as an opening move tells the kid that telling you costs him everything.
7. Write down what you've seen. Dates and specifics, in a note on your phone. It helps if you do need police.

Then keep the door open. The first conversation rarely gets the whole story. The tenth day of you staying steady might.

Teachers, coaches and youth leaders often see the shift before parents do. The signs a teacher sees before anyone else does is worth passing to anyone who works with kids. If you're not sure what's ordinary and what isn't, read the warning signs that matter, and the ones that are just being 14.

If you want to help beyond your own house

Support established organizations with a track record. Before you give or volunteer, look the group up. In the U.S., check the IRS Tax Exempt Organization Search and an independent evaluator like Charity Navigator. In Canada, search the Canada Revenue Agency's charities listing. Read the financials. Ask what share of the money goes to programs. Be wary of anyone who wants cash fast or won't answer plain questions. And never take part in anything that asks you to "investigate" or confront suspected traffickers yourself. That's work for trained professionals.

Where to report

Report online exploitation of a child to the NCMEC CyberTipline at report.cybertip.org (in Canada, Cybertip.ca), and take any concern about a child to local police.

You don't need proof. You need a reason to worry and the nerve to act on it. A report that turns out to be nothing costs everyone an awkward afternoon. One you didn't make could cost a child far more.