SO I went down to my local dollar theater to catch the Lego Movie, and Liam Neeson was one of my favorite V/O actors for the movie. Mainly because in his good cop bad cop roll he was unafraid to pitch his voice higher for good cop. At first I was simply impressed because this "serious, respected, academy award nominated actor" was willing to be so silly, but then it donned on me... the guy has two sons. Chances are when they were little and he'd play with them or read aloud to them, he would do different voices for characters. I know my parents did, and so do most parents in general.
Then again, this is the actor who, on the set for Star Wars, made lightsaber noises during all the Jedi battle scenes. Obviously, when he's in a "fun" roll, he's going to have fun.