Esther's response was reported to Mordecai.
Mordecai told [the messenger] to reply to Esther, "Don't think that you will escape the fate of all the Jews because you are in the king's palace.
If you keep silent at this time, liberation and deliverance will come to the Jewish people from another place, but you and your father's house will be destroyed. Who knows, perhaps you have come to the kingdom for such a time as this."
References for Esther 4:14
Esther sent this reply to Mordecai:
"Go and assemble all the Jews who can be found in Susa and fast for me. Don't eat or drink for three days, night and day. I and my female servants will also fast in the same way. After that, I will go to the king even if it is against the law. If I perish, I perish."