Unfortunately you can't force someone to report something like this. While it may be the right thing to do, you person assaulted needs to come to be ready and prepared to do something like this. Sexual assault can cause PTSD. Having to relive this event over and over to explain the stories to all different people can be draining as well as painful for the victim. The best thing you can do is to support and love them in this time. You may not fully understand what they are going through but being there as a comfort is amazing!
You cannot force someone to report a sexual assault, even though you mean well it might not be the right thing to do in that particular situation. Instead, the best approach to take would be to thank the person for confiding in you and ensure them that you will always be there to support them. The next step you should take is finding out about organisations local to you that may be available to help you both through this challenging time. Rather than focusing on reporting the sexual assault, it could be advantageous to focus on healthily expressing your emotions, doing a pregnancy test and getting checked for any STIs.
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