Whenever there is an interesting noise, Fleur looks to someone else and does the shocked expression. Raised eyebrows and narrows the lips. Then she turns that into a smile into a smile when I make the “Whaaaaa?” sound.
She does this to loud trucks, someone opening the door, noises from another room, and (of course, my personal favorite) farts.
The world should probably be terrified that she acquires my sense of humor. Early signs tells me we are going to have a lot of fun.