Letter to assistance program for caretaking tenant

[Chase Farley]

Hello,

My tenant has been a caretaker for his brother for the past 6 months, and his brother has been living in the unit. His brother is going to rent his own place and needs a letter from me stating that my tenant was taking care of him.

Is there a form letter to fill out? Is there any details that should be put in or left out? Are there any legal concerns that I should be worried about?

Thank you!