The third parent and the unfortunate side effects.

Marianna has a third parent.  It's not one we've chosen or she's chosen.  He often scolds her for things that she's doing, like helping him empty the dishwasher, not wearing shoes outside when I've said it's ok, eating a cheese stick I've given her, or holding the fridge closed so she can't get the milk-just to name a few.  Usually she has permission for all of those things-she was getting the milk out so I could pour it on her cereal.  He's a bit overzealous in his endeavors to be helpful resulting in two not so great side effects.  First, he often gets asked with rather annoyed parents, "Are you her parent?"  Of course at 10 he answers, "No." Followed by, "Did I ask you to do that?  Is she breaking, hurting or endangering herself or anything else?" Again with the response of, "No."  The conversation usually ends with, "Unless those things are happening and you can come get one of her parents.  The second (which accounts for the annoyed parents) is that Marianna's response to her brothers meddling is a high pitched wail, followed by crying.  This is also becoming a prevalent response to anything she doesn't like.

So while we love our "third parent" and often find him helpful, we'd rather Aiden stayed as his sisters 10 year old brother and left the parenting to us.