You're right. It is difficult to understand what is going on in the mind of young children (in your case, the girl is 7 years old). I believe that at this age children begin to be more aware of what is going on around and they ask many questions. "Why is this happening?" "Where do the children come from?", "Who do I want to be?" and so on

I think that earlier the children had fewer problems. Although I can be wrong. At such a young age it is important to give the child the opportunity to reflect on the answer. What they could understand what is good and what is bad. For example, studying, she definitely should bring the child joy. It is important for children to receive a good education. Best of all, they would like to do it themselves.
The childhood period is the most magical time in a person's life. It is important that the child would be interesting and joyful. You have beautiful and beautiful girls! I liked your message, it was interesting to read! Thank you