You can probably find an attorney around your area, if you look in FloridaBar.org.
For more information on your situation visit the link I'm attaching below for Florida Family Law Forms. All forms have instructions. Although these types of sources are very helpful, they sufficiently substitute the advice and guidance if an attorney.
Look through Domestic Violence section of the website, for you to gain insight.
Then trying contacting an attorney around your area.
Please call a local lawyer in your area. you an find plenty of them on AVVO. Good luck!
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Contact your local law enforcement to report this behavior. Make sure you save copies of the threatening emails, texts, voice mails, etc. from your brother-in-law. And contact a local attorney to guide you through the process of obtaining a restraining order.
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