Sister Is Threatening To Civil Sue Me For Filing A Police Report

I was owed a refund by a company and they issued it on a prepaid debt card and mailed it to my home. After 2 months of not receiving the refund I called back for an update and the banking company they used to send it said it was delivered and there's only 2 dollars on the card. I have some forms to fill out to report it as fraud because I did not receive any money. They sent over a transactions list and I looked up some of the businesses where this card was used at.

One transaction was made at a deli at my sister's job. Another one 3 days later was used at another deli across the street. Looking at the dates and some of these transactions they aligned with what she was doing. For instance, she texted me on Nov 8th saying she was going to Target and if I wanted anything. The date the transaction for Target and the time it was posted align with the timing she left the house. I know this sounds like a coincidence but there's other evidence and events that happen to not suspect it was her using the card.

After an argument, she obviously outright said she didn't do it. So I told her I have to make a police report they'll investigate the charges and work with the company to get my money back. She exploded saying I'm ruining her life and everything she worked so hard for. She threaten to take me to court for falsifying a police report to make it seem like she stole the card. What I told the officer was, what happened where I was and who I believe took the card. I explained I was in DC the day it was mailed I showed him my train and hotel information and the card's tracking information. I didn't get home till Tuesday night and the card was delivered the day before. Someone started using that card that Tuesday morning and I believe it was her because she handed me junk mail the following day when I asked her did anything important come for me on Monday or Tuesday she said no. For whatever reason, my mom gave her the only key to the mailbox so she only has access to it.

Long story short, I received a cease and desist letter from her "attorney" and now I have to go to mediation at municipal court for harassment. She told me her next step is to civil sue me for harassment and lying to cops because I included her name in the report and made this story up to get money from her. On a legal standpoint, is she allowed to civil sue me for filing a report and telling the cops I suspect it was her? We haven't been communicating at all so I'm not sure why the harassment angle.

I do want to add I did try talking to her and getting her side of the story instead of outright accusing her. I do love her because she's my sister I wanted to give her a chance to be honest with me and pay me back. The only thing I said with regard to paying me back was if she told me she took it she has to pay me back or I'll have to make a report so the company can see it was fraudulent and not me making these transactions.