Mom in trouble

Overall I like this app. However there is an icon that links the iPad to the TV in my living room. My 3 year old son found that today. Once he saw what happened he wouldnt let me figure out how to turn it off. There should be a parental control with password that asks if you want to link to the TV before it does. I finally got him to go to sleep. Im not sure if he found this by accident. I found it by playing with it myself. I was able to turn it on and off but if he finds it again Im in trouble. He will not let me turn it off he will have a temper tantrum if I do. A simple four digit code numbers or letters or mix would suffice and help me out a lot.

Mom in trouble about YouTube Kids, v2.19.13