Why do kids call their parents by their first name?

I guess all households are different in their own way. Some parents may allow it, and others may not. It's probably to feel equal to one another.

My parents, due to my sister's careless actions, were put in a situation where they were strongly recommended to foster my nephew and then a year later, adopt him. When he called them by their first name instead of "Omi" (grandmother) or "Grandpa" - It upset me. I felt like it was a sign of disrespect. My mother is a social worker- so luckily I had her and when we talked, it made sense why they didn't force him to call them a particular name. He needed to work out, in his own head, how to come to terms with the adoption and what it meant to him and who everybody was to him. Was I the aunt or the sister? My mother his mother or Omi? Was my dad his dad or grandpa? - It took months and a name change, but he ended up putting us all in different roles. He wanted me to stay his aunt/best friend. He wanted my mom to stay Omi and he wanted grandpa to be a mix of dad and grandpa because even when he was with my sister he never had a dad. This might not work for everyone, but it worked/works for our family. It's all new to us all and to force my nephew to stay in the restricted roles of being a "normal" child isn't going to work or strength the bond we have in our family.

Kids do so with their brothers and sisters, so they view their parents the same way! They know them!

I think a lot of kids do it to feel like adults themselves. They want to feel equal, and calling them by their first name puts them on a perceived same level.

Kids don't really call their parents by their first names, but if they do, it is very disrespectful. It's like calling the President by their first name, imagine saying "hey Obama wasssup", doesn't sound right does it? lol

Possibly to break the connection of them being their parents. Or maybe it is just something both the parents and children feel most comfortable with.

Kids sometimes call their parents by their first name because they have a more casual, friend-like relationship with their parents. In other words, their relationship with their parents is much less formal than others who call their parents by Mom and Dad, Mother and Father, etc.

I personally did it because it's a mutual respect thing. We were on the same level. My parents weren't above me, we were equals.

From personal experience it us due to the feeling lost from them. This can be due to emotional breakdown or a mental illness has caused this. They are still very much with love but not with the same respect