Standard user problems

Hi everyone,

I have an admin account and I set up a standard account for my partner.

1) Why when I update apps through the apple store on my end am I asked her apple store password? (I have also set up a family Icloud where she is a guardian and myself, organiser and guardian).

2) Why when it goes to sleep on her account it then shows "system administrator" as a username instead of her usual username?

3) When I unlock the username and group settings on my administrator account, I cannot change anything on her profile, is it normal?

I am wondering if she installed something malicious...

Thanks for your help.