I think as long as you have a good relationship with Emma and a strong grounding with step up and can read her body language things should not become too bad.She may become a bit more assertive but this is quite normal.I had very little trouble with Charlie ,maybe the odd nip but nothing serious.I have noticed he is a lot more distructive lately,he is 6-7 years old now. I think this is also normal for a bird his age. I dont know if gender has any reflection on this,I suspect its more the environment and upbringing they recieve.