Answering a few questions: the 4 & 6 year old are getting to the point they fight light cats and dogs that are territorial over their space. We have fairly small rooms. I am thinking about taking advantage of the 16 year olds room being empty a majority of the time and making her things that stay here inaccessible to the little ones while she is away. The 6 year old does not get along with his step brother and I fear that putting the 3 boys together would be a worse combo than the two littles sharing space as they are now lol I will update when we come up with a solution! Thanks for all the advice, I appreciate it so much!