The first step is locating him, and for that, you need a little more than just a name. There are about 2.4 million people incarcerated across the country at any given time, and no inmate search system can reliably find someone on a name alone. At a minimum, you need the state where he is likely being held, and his date of birth helps narrow it down further. If his sister told you he is in a specific facility or state, start there. InmateAid's inmate search can help you run that down once you have a state to work with.
Once you locate him and have his inmate number and facility address, you can write to him the old-fashioned way with paper and a stamp, or use InmateAid's letter service to send something through the site. Either method works fine. As for whether he reads it or receives it, there is no read receipt for prison mail. You send it, it goes through the facility mailroom, and if nothing flags it for review, it reaches him. The only way you find out he got it is if he writes back or calls.
On the Western Union question, most facilities use a different system for sending money to inmates, often JPay, Access Corrections, or a state-specific platform rather than Western Union directly. Once you have his inmate number and facility confirmed, you can look up the approved deposit method for that specific facility on InmateAid or by calling the institution.
Do not overthink the letter itself. Write it like you would want someone to write to you after a long silence. That is enough.
Thank you for trying AMP!
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