Need Advice: colleague yells at my students

I teach grade 7 and we are generalists at our district: we teach almost all subjects. Like most teachers in our grade level, teaching how to be decent humans is a large part of my curriculum. This is basically social emotional learning.

I've always felt it necessary to ask a fellow teacher before admonishing their students, as I respect that they have their own way of guiding their students. It is their classroom. This year, a colleague who teaches the same grade level has been appointed 'teacher in charge' for when administration is out of the building (both principal and vice principal.) I'm fine with that appointment for the most part.

However, my colleague can get quite angry with my students at times, and they will use an extremely loud voice to reprimand them with an angry tone. They never consult with me first. It's always a surprise and takes me off guard. One time I came back from lunch and she was in the room glaring at my class. All of the students had their heads down and a few looked frightened (one student told me they are afraid of her). The students told me they were "yelled at for being too loud", but when I asked my more honest/impartial students, it seems they weren't beyond the sound level we determined is 'too loud.'

Another day she called a big lunch meeting for all grade sevens in her room without talking to me first. She announced this by interrupting my class, stepping one foot into my classroom suddenly and yelling, "HEY! MEET in MY ROOM AT LUNCH!" with a very angry voice. I ran after her into the hallway asking, "Hey, what's up?" trying to smile and bring the tension down. She said she was disappointed in the way my students have been acting by being disrespectful to each other.

This was news to me, and I later found out it was nothing really at all - it was just the boys and girls not wanting to sit or play politely with each other (as they tend not to want to do at that age.) This is something we are working on, and I thought we were making good progress.

So my main question is, where do you have your boundaries set for letting your colleagues yell at and reprimand your students? To me, it feels like my colleague thinks she is my boss and is in charge of all the students because she is 'teacher in charge' when admin is absent. And I need to have a chat with her and let her know my boundaries.