send them a postcard with your number

This is in the hands of the original sentencing judge. If there is a REALLY good reason, he might get another chance.

Shampoo, soap, and other toiletries are provided to the inmates. Commissary has a selection of upgraded, or brand-name products for sale if the inmate has money on their books to shop. If you were going to help, put some money on their books.

Felony gun possession is federal and is a mandatory 5 year sentence

An inmate can reject their incoming mail if they choose

Try the inmate locator for the Texas Dept of Criminal Justice (https://inmate.tdcj.texas.gov/InmateSearch/start.action)... inmates get moved from time to time for various reasons, some transfers are for positive reasons even.

If you are referring to the California Inmate Firefighters Program, they could be out in the forest for weeks at a time during the heaviest season.

This is a slippery slope for sure... He needs to separate himself from this group if he is hanging with inmates who are still looking to break laws even while incarcerated. But if he's running with this crowd, he's gonna be guilty by association even if he declines. If he's truly serious, he really needs to do whatever he can, including seeking a transfer, to not be in a position where additional charges get tacked onto his sentence.

Most inmates on transfer might spend a night or a week in the SHU awaiting a bed in the facility. The situation you are referring to is called "separatee", where two inmates are either co-defendants OR "they know each other" and are required to be segregated. There are two types of segregation outlined by the Bureau of Prisons: disciplinary and administrative detention. This one is administrative.

Inmates have a lot of time on their hands and filing court cases is a common occurrence, including divorce. The court has to assist with an investigator to serve the papers