My sister is teaching at school X and she applied for a job in school Y. She was given a written test, and after being selected she was given an Interview also.
However, due to disciplinary code between school's association both school belong she didn't get the new job. School Y said, "Would have selected you but can't because it may cause trouble with school X".
Now she will go back to school X and is getting worried about handling this situation with the school's principal. She is presuming the principal knows because some other colleagues knows about this.
How can she politely and professionally handle being prompted about this situation by the school's principal or staff?