There are a lot more questions to be asked.
Are all females spayed??
Your Rotti is a bit old, how old is Mini??
Minis breed may have a lot to do with this, they don't know their size.
The fact that they are females is a huge part.

You cannot decide who is Alpha, except that you are Alpha, don't you try to figure out who should be and shouldn't. You are top dog, what you say goes.

Are they on leashes or free roaming??

How are they all greeted by you?? Must they obey a command to get some loving??

What more can you tell to the story??