My elderly mother has b1/b2 visa appointment at Chennai in July. Can someone please telle me 1) do I need to get any medical exam done 2) will I be allowed to accompany her 3) she is fluent in Hindi only - how and when should we ask for interpreter
No.
You can request the attendant atcthe consulate at the time off admission.
Generally you request while setting up the appointment.
Call VFS support and discuss further for more clarification.