How old is Pickett?
Is she currently going through a molt?
Has she come into condition?
If she is molting and/or in condition, then her behavior may become more aggressive.
It's important you keep a close eye on her to ensure she doesn't become overly aggressive or bossy with Phoenix. If she does, then it would be best for you to house them in separate cages and only give them supervised out-of-cage time together for awhile.