Another Tenant Issue

[Manco Snead]

Greetings good people,

Wondering how you would approach the following situation:

In one unit (2 bed/1 bath, class B/C) of my OOS duplex lives a middle age woman and her 8 yr old son on section 8. I dealt with this tenant's advocate friend from their church alot before I hired a PM for this property. This advocate friend has contacted me asking if the tenant's older (maybe 30) son can move into the unit with her as the tenant is having health issues. The older son has some past legal issues (don't know specifics), but according to the tenant's advocate friend they have maybe been "resolved." The current tenant has been ok, not great, paying late sometimes.  

I believe in working with tenants but don't want to create a mess for myself. Given that I also have a PM, how would you approach this situation?

Much thanks.