Answer:
This is probably because Ashley is aware that the context of their communication has changed.
Step-by-step explanation:
In communication, context refers to the setting where the interaction takes place. There are four basic aspects that influence the context: physical, cultural, social-psychological, and temporal aspects. They impact what is said and in which manner.
Being alone with her friend Leah probably makes Ashley more comfortable than being with her family. Friends usually know each other very well, share secrets, laugh at silly things and so on. Ashley doesn't have to worry much about her behavior when she is around Leah. However, with Leah's family, she probably feels that she should cause a good impression. She will be more careful with the things she says, might even express herself in a more formal way.