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Does your teenage son or daughter disappear for a couple of days?
Do they leave the house early in the morning and are they picked up by someone in a car or even a taxi?
These could be tell-tale signs that they are ensnared in county lines drug dealing.
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That's the warning from Families United, the Dover-based group set up to help counter the scourge.
Now it has organised its first public meeting to reach out to and support other families affected.
One of the six founding members, Jo*, told KentOnline: "Everyone needs to know about this problem, and that it can happen to anyone, even the nicest families.
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"These gangs are like businesses and have tightly run operations."
County lines is the system where gangs in big cities use youngsters in provincial towns and rural areas to sell drugs for them.
Families United, formed last August, has set up its meeting to encourage other affected families to come and get advice and support.
It will take place on Saturday, June 8, at St Radigund’s Community Centre in Poulton Close, Dover, from 6.30pm.
Guest speaker will be Kendra Houseman, a former London gang member who is now a consultant on gangs and child exploitation.
The event is for adults and young people from 13 and up although under-13s can be brought at their parents' discretion.
Steve, another of Families United's six founding members, said: "We want to help out other families.
"When it happens to you, you don’t know who to turn to and you feel ashamed."
Usually it is youngsters aged 15 to 17 ensnared in county lines but the group says that one 13-year-old is known to be involved in Dover.
Families United believes more police are needed to deal with the problem and there needs to be more provision for the young such as youth clubs.
Steve said: "There are not enough police on the street and the most youth clubs have been shut down.
"But we also need better education on drugs from as young as Year 7 (11 to 12-year-olds)."
Families United says youngsters can fall prey to the gangs in a vicious circle when, for example, they are excluded from school.
Jo explains: "It means the devil making work for idle hands."
Families United is at present focused on county lines but is broadly to help the mums and dads of troubled teens.
These are ones not only vulnerable to exploitation by gangs but also at risk of misusing drink and drugs.
To get in contact with Families United, see its Facebook page under familiesunited2018 or email familiesunited2018@gmail.com
* Families United members have not given their surnames to protect the identities of their children.