I have read "Where is the Mango Princess" and just learned of two other books that might help me cope and understand what he is going through. "Over My Head" By Claudia Osborne and " Brain Heal Thyself" By Madonna Siles.
The book I found most helpful is, Brain Injury Survivor's Guide: Welcome to Our World by Larry Jameson and his wife Beth Jameson who is the TBI survivor. It is a must read that will help you see exactally where the TBI survivor is at.