I recently met a pediatric cancer survivor. He had been subjected to the full range of chemo and radiation therapy. The damage done to his nervous and endocrine systems was incredible. He is virtually blind and nearly deaf but he can communicate with people pretty effectively on a one-to-one basis. At age 17, he was just a little shorter than my 5 year old and was operating on about the same mental level. He will never develop beyond his current abilities.
Considering that this was considered a good outcome, I can't blame the Navarros for seeking out alternative treatments.