I think they can probably hear each other, hence the screaming. The bedroom doesn't have heat, so I can't put one in there until it warms up some more. I will cover them in a couple of minutes when I go to bed.
Simon is a Mini-McCaw. Piper(I changed it from Pickle) is a Green Cheek Conure. I was told the Conure was a boy, but the cheeks aren't really very bright green, so I wonder if it is a girl.
Do you have any idea what the bobbing of the head conveys? It does not seem aggressive, but they both just bob their heads up and down at times kind of like you were saying yes.