The only thing that concerns me is if he is being dishonest. This is something that needs worked out and he needs support otherwise it will keep happening, he needs to know he can come to you about it if hes done something wrong or needs strength. If he cant do this then it will be really hard to overcome this.
You need to talk to him and try to sort something out, he needs to know you wont freak out if he comes to you for help though.