It is only natural for children to be curious about their parents' salary or financial status. It is equally natural for them to compare their status with peers and relatives. If they know that their parents have a fat salary, they can make certain demands like a foreign holiday or buying a luxury car. In case they find their parents earn little, it could be a source of low self-esteem. In both cases, it's not advisable to share earnings with kids. However, if you feel your kid is ready to understand financial matters objectively, you should give them a fair idea of what you earn, and assess their reaction to the information.
Discussing salary or matters of finance with your kid could be tricky territory, especially if they are young and could misunderstand or become anxious about financial issues. Every child is different and their speed of learning or attaining maturity could differ. However, there is a right age for everything and parents must tread carefully when it comes to exposing children to the realities of life.