One of my greatest joys lately is sitting with them and just listening to them go back and forth with each other. Clint and I taught them that as long as it is fun for everyone, it can continue. As soon as it stops being fun for one, it stops being fun for all. The one can remove themselves if they are offended. This has developed some strong, good natured. and playful relationships as well as thick skins. Very, very, very rarely does the playfulness go too far and as soon as someone speaks up, it stops and apologies are given. Then the play resumes in another way.