You are an adult and don't need a lecture, but I've seen this go wrong for so many people. 

They also achieved a by-law that precludes more than four (4) unrelated adults from living in a dwelling unit.  

I personally did not get into real estate to have a 2nd and 3rd job following after my tenants like adult daycare. 

I have lived in the Inland Empire "Corona/Riverside" for most of my adult life 27 yrs.  

I tell people it is like "Adult Monopoly". 

If you give her the same information as you did her brother, she might begin to see the light.Whenever it's a probate or willed property with siblings (who are adults and have kids of their own) that always seem to run afoul for investors.

I put on the lease the number of adults and children that are on the lease and that no more should reside there or else I can terminate the lease. 

Were any of the other members of the household adult?

I am over 800, and have been there most of my adult life. 

Since we were still young adults, we thought we had it all going for us.