Tenant has 14yr old from previous marriage move in

[Chris O.]

I have a 2 adult/2 kid (6/9) family living at my 3bed/2bath rental for about 18months. Rent is always paid on time, and while the family is messier than I like, they are not dirty (more laundry and toys etc everywhere in the house than dirty dishes piling up). He just told me his 14yr old daughter from a previous marriage has moved in. On one hand, I'm not overly concerned, on the other hand, I now have the additional wear and tear a teenager/extra body will bring to the property. Wondering how others would address this. I don't think I'm in a position legally, nor do I want to, refuse the situation. However, I'm not sure I can just leave everything as is.