My DD9 knows that DD7 is smarter than her and she was OK with that (most of the time). No. 4 is not the only reason but one of them, at least for now.
We are monitoring their progress and we may change our plan if necessary. Most of the people believe that teaching/tutoring other kids won't help for gifted kids. But we want them to become well-rounded individual and develop leadership skills. DD7 is doing it on her own and we don't want to take that away from her. She felt the classes in school are too easy but she did not feel bored because she always find something to do (helping the teacher do correction, etc...) When she starts losing interest, we will switch to our plan B or C.
