I was just recently wondering how Bettie Blue and Boo were doing, I am sorry that they are causing a bit of ruckus. Since I do not know the layout of the appartments I do not know if this would work, but is there a place that BOTH cats can stay for the night that is NOT above the down stairs neighbor's bedroom. This way they will not pine for each other, they can possibly still play a bit, but most of their running would NOT be over her head. ( I know, this is a lot to hope for)