One children get to a certain age (usually around two years of age) they begin to absorb everything around them very quickly and very easily. This includes what’s on television. I know many people who carry on watching what they like, regardless of whether their young child is in the room or not.
Not all daytime television is suitable for children. For example it might include adult themes which children are unable to deal with at such a young age. There could also be violence and/or swearing which could lead to the child repeating what they see.
Television is one of the easiest ways for a child to learn. Therefore you must make sure your child isn’t watching something that is not right for their age group, otherwise they will learn stuff before they have the proper mental capacity to deal with it properly.
Well your child it still under a year and a half this is pretty much an non existing issue. Above that age you have to be careful, even if they aren’t paying attention to what is on the screen because that can change in an instant. Once the damage has been done it can be very hard reverse and then you'll have to live with the consequences.