My son has once again gone against the house rules of not smoking pot at the house and having a particular drug friend over. So he was previously told that the next misbehavior, he would be sent packing. The problem is how we found out: our older daughter showed us his snap chat : break time at work: smoking bong and in our back yard with his friend with a bong. I say so what to how I found out, now he has to go, but my husband says that if we do kick him out he will know that his sister swelled on him and that will harm the rocky relationship that they already have. So do I let my son keep spitting in our faces to save the sibling relationship or do I put his to a halt. Please advise.