Is he mad with his best friend? Or only seems to be punishing his sister?

TBH, beyond the obvious malicious part, the anxiety of your son, I would be concerned this is be a slippery slope into some unsavory internet communities where he blames everyone else for the consequences of his anxiety (which to be fair, are NOT his fault). But focusing on maybe a different or new/additional psychologist/therapist might be the helpful/productive way forward to helping your son learn to cope with his feelings.

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If you target the core issue and not just the symptoms (stealing glasses and jealousy, etc.), it will likely solve the problem and help your son more down the line.