Should I be Concerned

My 10 year old sister plays Roblox, and every time she leaves the game on for a few seconds to do something(use the bathroom, get a snack), she always puts the camera in first person, points it at the floor so not other players can be seen, and turna off the chat. I think she may be online dating(something Roblox is very well known for) or doing something bad. Any time I join a game she's in to see what she's doing, ahe and her friend kind of bully me with admin commands(killing me, freezing me, jailing me). Should I be concerned?