Sorry no response till now, everyone has snoozed off, As I see it some of this behavior whilst not nice does happen and as it was a while ago maybe you need to let it go, but be observant and be around with them as much as you can, it is your husband who should tell his 6 yearold that the behavior is inappropiate behavior,it is possible it happened to him as very often this is copied or he saw something bad on the Computer or in an adult magazine, however let your husband deal with it, If he hurts your 4 year old you should tell him that he cannot do that and have a talk with him about it,Dont tell him to do things ,ask him, and try to focus on the positive side of his behavior, praise him when he does something right,its possible he needs some extra attention . How about Dad being involved in Sports and Games and outside activities for both Boys