Please, please, please feel free to ignore this but - in your shoes - I would try Ferber. DD was a terrible sleeper. I waited until 8.5 months (and me going INSANE) and it was shockingly effective, fast. I really wish I'd tried it earlier, for all of our sakes. Including her, she was better off getting that rest. For us, it was a completely turnaround after less than a week of charting. I believe Dr Ferber recommends it for 5.5 months and older.