My grandson is 4. He still speaks w/2 yr old mumble level. After MANY exhaustive trys, he was diagnosed w/fluid behind ears and heavy wax buildup on eardrums about every 3 months...therefore he was never able to hear anything but muffled sounds! We now have tubes in his ears to drain fluid and every 3 mos doc cleans out wax. He has been in speech therapy for 6 months since, and he is speaking 500% better!