This advice-column-style blog for SLPs was authored by Pam Marshalla from 2006 to 2015, the archives of which can be explored here. Use the extensive keywords list found in the right-hand column (on mobile: at the bottom of the page) to browse specific topics, or use the search feature to locate specific words or phrases throughout the entire blog.
Q: Do you think that enlarged tonsils and adenoids are related to the lateral lisp?
We have no data on this as far as I know. I have seen a few kids where I thought these problems were inter-related. But I would not suspect that all tonsil/adenoid problems cause lateral lisps, or that all lateral lisps are caused by tonsil/adenoid problems. I think you have to determine this for the individual child. We must ask ourselves: Do the tonsil/adenoid problems seem to be related to the lateral lisp for this child? If so, then something must be done about them, or we have to teach the child to compensate for these structural problems, i.e., teach the child the best sound he can make given his situation.