Why do kids call their parents by their first name?

Maybe because they don't feel like they can call them mom or dad. Or they don't feel like that is their mom or dad because of the way they are treated.

Some kids call their parents by their first name because they might not be lucky enough to have a close relationship to their parents enough to refer to them as 'mom' or 'dad'.

I am not 100% sure as I am sure it is different for each person but I DO know that one of my close friends calls her parents by their first name at times because she was adopted and does not feel comfortable calling her "mom" sometimes. Especially when stress is heightened within the family at the time.

It's doesn't seem 'cool' anymore to call parents 'mum' or 'dad' people at school might tease you about it

Sometimes children are taught at a young age that they can call their parents by any name (i.e. Mom, Dad, or first name.) if that isn't the case sometimes it's a way to show disrespect which generally occurs among teenagers. The last case I can think of is if the parent is a step parent. My friend's mom married a new man and she refers to him by his first name. There are many reasons, but I believe these are the main ones.

This could be because they just learnt the name (when kids are young) and think it's funny. But often in plder kids this coiuld be because the kid doesn't feel close enough to his or her parents to call them by mom or dad.

Kids feel comfortable enough to be on a first name basis with their parents or view their parents as an individual instead of attached person. Older kids tend to call their parents by first names before younger kids due to the understanding of this concept. This can also be translated into a negative feeling of disrespect because of the lack of acknowledgement that a mother or father has given life to that individual. The interpretation of this is solely based on the discretion and attitude of said parents and their willingness or unwillingness to allow their kids to make this transition.

That's a great questions. It could be for different reasons. Maybe they are going through that phase where they feel the need to go or even do the opposite they are being told. There's nothing wrong with calling your parents by their first name. Perhaps, talking to the kids, and asking them why they do it might give you those answers you need. On the other hand, maybe they want to have a more casual relationship with the parents, maybe they want to treat them as they treat a friend, or even a cousin for just to set an example.