★★★★★
Two boys I know *solved* their poor pronunciation (one was moderate, one was really serious--couldn't say half his sounds correctly) after going to the chiropractor after noticing that their heads/ necks were a little out of balance/ awkward.
The more serious one had been that way for years, the moderate one had been that way for a few months due to a bicycle crash, though he couldn't really feel that there was a difference--a slight massage run up the neck with fingers produced pain and helped detect it, too.