Cameras in the kids rooms?

I’ve been babysitting for a long time, but I’ve only ever seen cameras in babies rooms. The parents I’ve recently been sitting for have one in their baby’s room, had one in the basement that I kinda just found? one day? it was in plain sight, but I never noticed it… I was never told about any cameras. Recently, they put a camera in the older boy’s room and it’s also in plain sight, but I don’t know why it’s there. I was never told about any medical issues and the camera is pointed at his bed.

Is there some reason I’m not thinking of for why the parents put a camera there? Is this normal?