CREATE TABLE table_30747 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" TEXT, "U.S. viewers  ( million ) " TEXT)

Who wrote 'the diaper incident'?
SELECT "Written by" FROM table_30747 WHERE "Title" = 'The Diaper Incident'
SELECT "Written by" FROM "table_30747" WHERE "Title" = 'The Diaper Incident'