H.
We always had sleep disruptions when mine were learning a new skill such as crawling, walking, language burst, etc. It was like they just didn't have time to sleep since they were so focused on the new skill. They would be super grumpy, but refused to sleep. Once the new skill was mastered, they quickly returned to a normal pattern and everyone was happier. Of course, they work on so many new skills during that 6-18 month period that it was never long before another disruption occured.