Answer:
She conceals her true feelings of disappointment because she does not want to upset her teammates
Explanation:
Middle childhood can be described as the stage in the children development where they tend to experience more of the world around them, and begin to develop their own identity.
Some of the specific characteristics of children at this stage of development are,
* They show rapid development of mental skills.
* They learn better ways to describe experiences and talk about thoughts and feelings.
* They have less focus on one's self and more concern for others.
In this case, referring to the third point mentioned above,the child will try to conceal her true feelings from her friends because at this stage, she is more concern about other peoples feelings.