17yr old stealing from family

[Nickpan]

Takes cards from wallets, steal clothes from siblings (his younger brother hasn't seen his Armani jeans since he got them on xmas day), he's about to lose his job, keeps getting caught with weed, has been searched twice by police....
How do we break the cycle?

Oh god that's difficult. Does he admit to anything? Does he have any MH problems? Friends? When did he start this?

What does he do with the clothes? Sell them?

He ruefully admits it, if he's warned that other siblings will all be punished too... he has, oddly enough, high levels of loyalty in certain areas, maybe not toward older family. Massive loyalty to his friends, has admitted they are a bad influence on him, but he will not consider dropping them for a minute. I suspect he's anti-adult, which makes it easier for him to charm and con them. He could have done well in exams, but skived off to spend time with his friends who weren't up to the level of exams. He lost his mum in 2013 :(
Sporadic counselling, he says it helps, but he knows the right things to say, the right buttons to press.
He tells a good tale, and can wrap anyone around his finger. All other parents think he is an angel. All money in house now locked in master bedroom, but he is so on the ball, you only have to turn your back for a second. Actually pulled a brand new hoodie off his little brother's back to wear out. The xmas jeans have holes in, and 5 pairs of white socks that his little bro got for xmas, have not been seen since. Plus many other examples, ie, little bro travelled 40 miles to a big shopping mall, but some items snatched that evening.
Failing at his job, about to be sacked, all pocket money stopped in an attempt to get him to take work seriously. I.m concerned that his GP give him pocket money, clothes money, haircut money.

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